There are three QBs who profile pretty well in comparison to Russell Wilson: Fran Tarkenton, Drew Brees, and Doug Flutie. All three stood 6 foot and change- or less. All three used mobility and smarts to extend plays and avoid injuries. Brees turns 34 next month and is still going strong. Tarkenton played until he was 38. Flutie played until he was 43, and was 39 in his last season as a full time starter.
Russell Wilson has missed just 1 game from injury (week 2 of his freshman year) in five seasons between college and the pros, and hasn't even appeared on an injury report since 2008. In the Bills game he ran the ball 9 times for 92 yards and 3 touchdowns, and was never hit on any of those runs. Clearly this is a QB that knows how to protect himself. He may not be injury proof, but I could see Wilson as being one of the least injured QBs in the NFL during his time in the league.
I think based on the prior history of comparable QBs combined with Wilson's own history and tendencies, there is a very real chance that he could play into his age 38, 39, and 40 seasons. Remember too that he has speed/athleticism to burn, and those kind of players tend to age more gracefully in any sport. He's also a highly intellectual QB- the game slows down for him. Those types tend to play a very long time as well.
The current win leader is Brett Favre, with 186 wins. It's possible that Manning or Brady could last long enough to catch him, but that's where the record stands for now.
Let's say that Wilson has 15 more seasons after this one (16 seasons total). He would retire just a couple months after turning 39. His rookie season could have as few as 9 wins, and as many as 15. Let's split the difference and say he finishes with 12. If Wilson played 16 seasons and had 12 wins in 2012, he'd need 11.6 wins per season to tie Favre when Wilson is age 39.
Given how ridiculously good this current Seahawks team is, how good the front office is and how good the coaching is, that seems like an achievable goal to me. Seattle will probably rank #1 in DVOA whenever Amazon decides to get FO's servers up. Just three years ago they ranked #31 in weighted DVOA (iirc). Even Jim Harbaugh can't boast that big of a statistical swing in his team's fortunes. But I truly believe that we might still yet see this regimes best football yet to come. This team still has issues to iron out. Carroll has been a tremendous fixer and Schneider a virtuoso acquirer of talent. I see a lot of 13 win seasons in our future- with deep playoff runs.
Hell, if winning the Superbowl wasn't so hard to do, I might get cocky and cast hypotheticals on Joe Montana's record too. Wilson will certainly get a lot of chances- and he just seems like the kind of QB who will shine even more in do-or-die moments.