(this is a long post, scroll to the end for the tl;dr bit. Also it may not make much sense/be a bit wrong in places as I wrote it as it came to mind. PS: I am aware I may sound like a hypocrite to some people reading this lol. My blog I'll ramble how I want!)
The first thing I do most mornings when I turn on my PC? I check various Sonic message boards. And laugh at them.
Now, being a Sonic fan myself, the things I usually see in forums make me roll my eyes. People taking things so bloody seriously!
Sonic the Hedgehog is a game primarily aimed at children/young teens. But an alarming amount of the fanbase forget this and read far too deeply into the game canon. I suspect it's like this with any fandom, but honestly, it just makes me shake my head.
It's a bloody game about a blue, super fast, HEDGEHOG. WHY are you even TRYING to take it seriously?!
I'll leave the various comics/books/etc out of this argument, as they're all off in their own little world (and Chaos knows I have a dislike of certain ones and their soap operas) but the games are pretty much apart from each other. You can fan up your own storylines for linking them together all you like, but bloody hell people, your fanfics aren't canon, stop thinking Sonic 3 and Knuckles links PERFECTLY to Sonic Adventure 1 or whatever order the games actually go in (because it sure as hell doesn't).
The storyline after Sonic Adventure becomes slightly harder to define, because with the three main SEGA departments becoming linked, we all got the stories from the west and east together and ended up with a lot of confusion at first (SA1: OMG His name's Robotnik NOT EGGMAN BAWWWWWWWWWWWWWWWWWWWWWWWWW). But now they settled I'll try take a guess at the story order.
Sonic Adventure 1 leads to Sonic Adventure 2 (but I don't think the stories are actually related. Like, at all), Sonic Heroes follows on from SA2 in what I'll call the Shadow Arc, with Rouge finding Shadow in it. Also there's some Chaotix and Sonic and Amy flirting. Then it's Sonic Battle, followed by Shadow the Hedgehog.
Sonic Advance 1, 2 and 3 are all over the place I think, but Advance 2 must be before Heroes with Cream being a main character in it.
Sonic Rush and Sonic Rush Adventure are kind of on their own, with Blaze the Cat being an interdimensional travelling princess that has her own set of emeralds, her own Eggman, and the 'must stop dimensions going boom together' storyline.
Sonic the Hedgehog on the Xbox 360 ended up standing on its own, as it didn't really... fit in with anything, being the first attempted re-boot for the series. Sonic is a hero, sure, Shadow works for GUN like at the end of ShTH, and there's Silver, who... uh... travels from the future with Blaze. Wait. Blaze is from another DIMENSION what?! Yeah, Sonic '06 wiped itself from history at the end of the game so I guess it's okay to ignore it haaaaaaa.
Sonic Rivals and Sonic Rivals 2 I can't really comment on as I haven't tried playing them, but pretty sure they aren't related to the main storyline.
Sonic Riders, Riders Zero Gravity and Free Riders are a bunch of racing games that have no relation to ANYTHING hahah.
Um, then there's the Storybook games, which again, have no relation to anything, just fun stories on the side.
Then the series reboots again! Sonic Unleashed brought back the 'only Sonic' formula, split between faster daytime and slower night time modes with the Werehog. It was a pretty game and I liked it, but much like the two different forms of Sonic, there's a marmite divide on this game. But it leads on to Sonic Colours (apparently), which is hailed as one of the better games.
The less said about Sonic 4 Episode 1 though, the better. Nice nostalgia trip, but I wouldn't count it as part of the original series yet.
And as for Sonic Generations, back to my initial point of the stories being in different sets and pretty damned difficult to link together post Shadow, SG is going to be one big fat nostalgia trip and it's un-clear whether it'll fit in with the current storyline or be a stand alone game of it's own. With the writers from Sonic Colours on board, I suppose it'll be the former, BUT I'm not willing to play with the story in my head unless I find out more about the it before it's released. I'd prefer to wait until I get to play the game though XD
If the bad guy is Silver or an older Sonic, I will laugh at all the fan bitching, I really will :P Especially when they try think of OMG WHATS CANON IT HAS TO BE IN RELEASE ORDER (no, it doesn't. Sonic Battle and Sonic Heroes plotlines are in reverse to their release order, and as I pointed out, the storylines, or what little there are, are in different chunks). Also OMG SRS STORY NUUUUUU D:
SO YEAH. Fanbases can take things far too seriously, I'd rather people enjoy games on a game by game basis instead of trying to think how each game links to the last one released :P Oh, and to stop bitching games because it's cool. I liked Shadow and 06 myself, and I didn't like Sonic CD. TAKE THAT BITCHES :D
The internet is srs bzns. for reals.