I dont think its important how long you've been here (September of 2000, and I've been forum active ever since) but the ammount you've given back and the knowledge you've obtained.
Lets take two people. One is Indi, and the other shall remain nameless because it would be wrong of me to call this person out and put him down. These two both signed up around the same time I did. Indi, as we know, has given a lot back and has gained a fairly large knowledge base. If you've seen his examples, you can tell he knows how to code. The other can barely print his own name on the screen because he's too busy running his mouth on the forums, learning nothing.
But, anyways. For anyone who doesn't know me, I worked on Vapour-Racing with Webdext and Steve677. I worked with Webdext on our 1 level demo Vizor Xari. I have done several tutorials and demos, including my terrain/texturemap example, old school fire code, line-point collision, and AI. I try to contribute. Its nice to see a lot of the older people back.
I actually miss Semtex, he was a rather funny yet annoying distraction =]
Some older people I never see around: BigGun and Titan. BigGun I know has sort of faded out of programming, and I'm not sure what Titan is doing these days.
