Does the sentinels universe have a continual continuity like Marvel or does it have periodic continuity resets like DC?
I think it might be the latter. Wraith's bio lists her age as 23, just a year after finishing college and adopting the Wraith persona. However, she's one of the longest running heroes, having first appeared in Mystery Comics #27.
Doesn't that make it the former? Spiderman hasn't aged much over his years of superhero-ing.
There has been no hint at a reset, and a continuous numbered series like the Freedom Five seems to point at a continuing universe.
If I remember correctly, Christopher and Adam have both make comments in the past that it's a continual continuity.
Spider-Man went from being a high school student (around 16) to being in his 30's before being struck by One More Day.
Coolness!
Yeah, I was going to say, the last time I remember reading spiderman he was a 30-something school teacher instead of a struggling college kid (or teenager) like when he started out
Yeah, but it took Petey ~40 years to age ~15. 
Well, Marvel also has a floating timeline. Also, I think they've said that approximately 2 years real time passes for each year in the marvel universe.
http://en.wikipedia.org/wiki/Floating_timeline#Marvel_Comics
Sometimes it's closer to 5 years of reality to one in the Marvel U.
On a slightly relevant note, doesn't the Marvel U run on a "10 years ago the Fantastic Four #1 happened and we update our characters history to reflect that", e.g. Reed Richards and Ben Grimm fought in World War II. Then Korea. Then Vietnam. And now Desert Storm.
7 year sliding scale.
Yep. And Tony Stark was injured in whatever conflict America was involved in within the last 5-10 years.