Wow.
That is some change. I am hyped.
I'd imagine the story is similar for most here. I kinda missed SF2, I did play the cab at my local pizza place every now and then, but I was playing MvC1 and 2, CvS2, and 3rd Strike as a kid. I just didn't really learn or maybe I should say "understand" fighting games until SSIV and started informing myself on SRK, videos like Vesper Arcade's tutorial, and the original SF4 crowd here on GAF helping me out.
I'll second that story. I played a hell of a lot of fighting games in my past (SF2 on) but never really understood anything deeper than "use special moves, jump, punch and kick". Also, I always thought throws were super-cheap (unfortunately, I still do!)
All that changed when I actually started watching streams and spending time here and on SRK. The most dramatic change was when, after losing around 45 straight games online in Vanilla SFIV, someone either here or on SRK suggested that I just "put the CPU on it's hardest setting and try to block every attack. If you time out, you win!" So started my long journey understanding blocking, and how/when to use normals, and why special moves aren't the best to just throw out there.
I'm still not good by any stretch of the imagination (I think I have a 25-40% win ratio with Dudley?), but I'm having a ton of fun playing and watching streams. Much more so then I used to. I still don't understand certain character types (grapplers in particular), but I'm pumped to try and figure out Hugo when the next iteration of SFIV comes out!