Well I have just been playing Sonic Mania for the past three hours or so and been having a blast (sorry pun intended!)
Awesom-0 summed it up very well, I've got to Studiopolis zone and it';s nice to see the fan service and easter eggs, I'm gonna be spending a lot of time going through levels going Ooh...Ahh!
I really loved Chemical Plant Act 2's boss but I won't spoil it either but that was a lot of fun.
Special mention has to go to the effort they did with the statue for collectors edition, I have uploaded some photo's for those who may not
have paid for collectors edition, pride of place in my Sonic display cabinets!
If you put two AA batteries in the console base and hit the on switch it says SEGA like when you used to play an old Mega Drive/Genesis.
I'll add some video footage of the first level a bit later and the opening movie animation.