A for effort, but the vast change over time in labeling this Sonic 4 isn't appropriate
Well, No. It's a 2D sonic game, and the running controls are rather smooth, environments look very nice with the cell shading route, but everything else falls short or isn't even there. The story is a classical familiar: Robotnik is turning everyone into robots stop him, and it doesn't try to go further than that.
The gameplay is concretely the same in terms of design, but changed the physical mechanics. The original sonic games worked their levels and bumper placement of sorts around the famed Pinball mechanics, allowing you to use momentum to your advantage. Sonic in Sonic 4 episode 1 has no momentum, the game has literally transformed into Hold right to win, more so than it's predecessors. The change from pinball mechanics also makes the jumps in general more floaty, and they addition of the homing attack removes what little skill you have to posses to play.
Episode 1 has a total of 17 actual levels divided into 4 zones with 3 acts each plus a boss zone, and then the final zone. The levels themselves are rather short spanning about 2-3 minutes each, maybe more than that on your first playthrough of the game, ensuring that the game will be completed at a moderate pace(take a break, lunch, drink ect) in about an hour or 2.
Possibly the most tragic change in Sonic 4 is the soundtrack. Generally should a sonic game fail to impress with gameplay(which was pretty expected with 3D outings until colors and generations) one of the more redeeming factors was the soundtrack that accompanied the game. Jun Senoue has been working on Sonic soundtracks since Sonic 3 and has composed a large amount of music for the series as a whole. The large use of synthetic instruments equate most of the tracks to "dying cats". None of the tracks are particular memorable other than the mad gear tracks. If anything the wii has the better soundtrack compared to the HD versions simply because it uses lower quality samples that sound closer to the genesis.
All said and done, the changes can be remedied and soundtrack improved, but the core of the game is perfectly playable with no visual problems whatsoever and no technical problems as well. Assuming you have not played the originals, the gameplay will feel fine to you. Original players will notice the difference and have to take some time adapting to it. However Personally, the game was far to hyped for it's own good, thus my score given is a 6.