Just got mine today and the new cards are quite noticably smaller than the rest of the cards in the deck. Is this a potential concern for those playing? Considering it's a co-op game, I can't imagine the difference is game breaking, but it can give you a "I've got either an Embolden or a Chastise coming up next round!"
Mine are smaller and faded. I already emailed GtG about it, and I am waiting for a response (it is the weekend after all).
Tachyon's are perfect. Ra's are just a hair off. Fanatic's can easily be picked out.
I think it's going to vary from person to person. The original Enhanced Edition cards had a non-trivial variation in sizes. In my decks, I can pick out where the division between different shrink-wrap card decks are, and the one in the middle of Wraith's deck threw off shuffling substantially (before I asked for replacements). So depending what size your original cards were, you'll get different effects with the new errata cards, which are presumably of a standard size.
My errata'd cards are significantly smaller than my base decks. Like, a good full millimeter. It's bad enough that I've decided to not use them and just remind people that the text has changed.
So, this is a sucky problem that I see no good way to fix, unfortunately. As dpt mentioned, the original several thousand copies of Enhanced Edition had inconsistent card sizes. We yelled at the printer about it quite extensively, and they have been very consistent since then, but unfortunately that means that the early adopters of Enhanced Edition are going to find that their (consistently sized) errata cards stand out significantly if they don't sleeve them.
Yeah, another early 2nd printing here too. If shuffling is a problem then I'll probably just revert back to the original cards as the changes are not hard to forget, or one day replace with a new copy of the EE. In any case, it was the promo's that I was far more interested in so happy days 
Thanks, Paul. Greatly appreciate the info. It will be interesting to see how they differ (once I get them).
Sadness! I got mine today thanks to Mezike and was very excited to add them to my decks.
But it's impossible - I too got one of the mis-sized EE boxes (I had to get three replacement decks) and I hadn't even thought about the fact that this might be a problem - all of the errata cards are 3mm or so shorter than the originals. There's no way I can use them in any meaningful way. :( And there's no way my (mostly casual) players will remember the new rulings either.
Keep the new cards with the character, outside of the deck, for reference when they come into play.
Some of my players can't keep track of which is their deck and which is their discard pile and are utterly incapable of grasping the idea of laying down their cards in the order they were played, despite my constant reminders. (Believe it or not, otherwise intelligent people.)
I sense confusion in their future.
or trim the edges of all the cards that are too long?
Trimming about 100 cards to be even seems like it would be quite a bit of a hassle, don't you think so?
Yeah, it's only the errata cards which are too short - must be an EE Core Set thing, as the promo cards for Expatriette etc were the same size as the rest of their decks. I didn't actually think to compare a Rook City (or any other expansion) card to one from the EE to see if there was a size difference but I would presume there will be.
Incidentally, Silverleaf, the only cards whose played order matters are the ones which trigger at a specific time, which tends to be start or end of turn (matters most for Omni-10 I suppose). Anything else doesn't matter. So if they're playing pretty much anyone else it will be okay. I would have severe difficulty keeping track of the Adept if I couldn't lay out his cards in the order I wanted to (ie all instruments grouped together and then songs by type) ;).
Also matters quite a bit for Unity's bots. But those two are the primary start and end of turn effect heroes.
Yup, I use two different decks for Tachyon (one for Standard Tachyon and one for Team Leader Tachyon) and the decks were bought at different times... and the errata cards match the size of one but not the other.
I do the same for the two Ras and the two Fanatics .. but since their promos were available much earlier the second decks were bought earlier as well as replacement decks... and the errata cards don't match any of those.
Fortunately, I sleeve... so the differences aren't noticeable in games.
You're overestimating my players' ability to decide which cards matter in terms of order and which ones don't. It's FAR simpler to just give them the blanket rule of "lay down everything in order" rather than expecting them to grok the difference between those with specific timings and those without.
I'll worry about AA if and when anyone's actually able to play him! 
I was pretty disappointed when I saw how small the errata cards were compared to the rest of the deck. We're talking like 1/4 inch shorter which also means the art on the back of the card is noticeably scaled down and smaller. I noticed it right away but I decided I just wouldn't tell my friends about it so they won't know when one of those cards are coming up. As a true gamer, I can "pretend" to not notice when a smaller card is on the top of my deck.
1/4 inch? I thought the difference was two millimeters.
Regardless, it's enough that the cards stand out in the deck, which is unacceptible.
>G, can it be feasible to acquire replacement decks for the three affected characters at some reasonable price?
Mine are 3mm. Definitely more than 2mm.
But less than 1/4 of an inch.
In my experience, there is some variance in the error, and it can be anywhere from 1mm to .25"
So what would you suggest for all of us who are in this situation, Paul? My cards are probably only a millimeter or so off, but that's enough to make all the PtLs in Tachyon's deck instantly visible, and I see that as being a problem, so for the moment I'm not using the errata cards.
Sleeve your cards? If they're all sleeved in the same sized sleeves, it's much harder to see which ones are different sizes. Especially if you use ones with a coloured back.
I am not interested in using sleeves.
If imagine the only options available right now would be to either not use the cards altogether, use them by proxie (that is, keep the old cards in the deck but refer to the new text them when they come up), or buy a replacement deck for the affected decks.
You buy 100 sleeves for a dollar and just sleave the one deck you have issues with. You'd then have sleeves left over for another character if you had a similar issue. Also, sleeves work well for printed promos. Gives them a firmer texture if you printed them on regular paper.
The cheapest sleeves I could get here for my three affected decks would cost the equivalent of $3.75-ish. And then they wouldn't fit in the box...
My errata cards finally arrived this morning (they were on the slowest boat from St. Louis to California, apparently). The cards are slightly smaller than the rest in my decks, but I'm certain my wife and daughter will never notice if I don't mention it, so I'm just going to use them.
My errata cards are the same size as the ones in the box, given that I have a copy of the game with the new errata on it already this is hardly surprising but it good to note that the printers did something consistantly!
I was wrong. The first thing my wife noticed upon shuffling the Tachyon deck was how some of the cards didn't shuffle right with the rest of them. Now she's making me pull them out and put the old ones back in. Le sigh. I guess the errata cards aren't as useful as I'd hoped.