http://sonicjam.wikidot.com/nsssp:indexThis was posted over on Retro and it's worth a read. It's your standard page of arguments for what's wrong with Sonic today, only it contrasts said problems with what made similar things in the classics seem great, and it acknowledges the need for flashiness in a modern world where a game has to work damn hard to make up for the sin of using a color palette aside from brown, beige, gray, and black. Too bad much of the video footage doesn't load.
I can safely say I'm glad I read it. I'd already had a lot of those concepts in my mind due to designing a Sonic 2 hack, but the ones I either learned for the first time or was reminded of will definitely come in handy.
EDIT: The entirety of the site is
here, but a recent argument in chat made The Speed Zone seem the most relevant.