Well, I'm a little late to the thread (plus I haven't logged into bikeforums.net in nearly 10 years!
) but I also joined over at vital bmx as well. Adding to the age pool, I'm 36 and just picked up my first BMX bike in 20 years and probably the first bike I've been on for more than a few minutes in the last ten years. It's a Fit PRK, so 20" wheels and it's not so bad. I'm 6'2/175ish and I feel just fine on it, though it is twitchy and I'm trying to learn some control. It's a hell of a bike for bombing hills! With its responsiveness, it's more fun than my old Bianchi Nuovo.
I like it so much that I'm considering selling my remaining two bikes and picking up a 26" BMX cruiser for a multipurpose ride (light trails, town rides, urban terror, etc.).
Guess my opinion on the "too old" bit is that as long as you can pedal it and have fun, you're not too old.