I think they should definitely continue to make games like Sonic Rush which stay true to the original, particularly on portable systems, but I\'ve got to say - having only recently \'properly\' got into Unleashed, I think we\'re one addition away from a truly next generation Sonic game.
I thought some of the ideas that Unleashed introduced were great. Collecting medals (which opened up extra stages) was an excellent incentive to replay through existing levels, and the split between 2D sections and third person perspective areas was very well done. The day time stages (ie the reason you bought the game) were, in my opinion, extremely well designed and arguably as good as the levels in the originals! On top of this, the boss fights were very enjoyable (and not exactly pushovers), stupid additional characters were kept to a minimum and the cut-scenes were actually quite entertaining with the humour handled particularly well! 
Sonic Team actually got a lot right in Unleashed, it\'s just a shame they lumped half of a completely different game in there too - which I suspect they did because it wouldn\'t have sold as an IP! So I guess what I\'m trying to say is it would be a shame to completely abandon their new formula to go back to strictly 2D Sonic games now, it\'d be like abandoning an oil rig even when you know you\'re about to strike oil. 
The werehog sections, I reckon, really hazed people\'s overall judgement of Sonic Unleashed and I think if you were to play through just the day-time stages, you\'d be seriously impressed. I reckon not much would be needed to be done to make the sequel a hit with everyone. My suggestions…
Get rid of all humans and return to the original Sonic world - I\'ve forgotten what that\'s actually called. Stop introducing soul-less characters like chip and shadow and focus on the original cast - if anyone should be brought in, it should be the more convincing characters from the original cartoons and comics. No more gimmicks - no werehogs, no princesses, no telepathic hedgehogs changing the game formula. No more talking characters - silent Sonic was cool, every babbling rendition since has been anything but. Improve the music - Unleashed was ok, but lacked the charm of the original. Work on environments - this is something Unleashed was better at too, but still didn\'t achieve the lush next generation Green Hill dream that is perfectly epitomized in the picture Dark Flame posted. Wow.
That was a particularly long post. So I\'m going to reward you all in true dartmonkey fashion...
Edit - How weird is that? We actually picked out the same pair of breasts. Clicky. Sure, they\'re the nicest pair on the first page of google images, but it\'s still pretty amazing given the ammount of boobs on the internet.
... What?
( Edited 10.02.2009 20:06 by TheStratMan )