So! Here's the short list:
Pros:
-Lots of fun characters to learn and play
-The rift between top and bottom tier chars is not quite as abysmal as MvsC2
-Unlocking chars is not a huge undertaking
-Great flow to the combos, much easier to learn (I think)
-Easy game to learn, tough to master (as all good games should be)
-Difficulty levels are actually challenging, not cheap
Cons:
-Matchmaking/Netplay is horribly broken / fragile
-Missing a lot of features found in games like SSFIV (replays, character "channels", multiplayer modes)
-Some key characters are missing (Mega Man) while new additions seem unbalanced (Dante)
-Somewhat button-mashy (think Tats vs Capcom)
-Mission mode (challenges) are fairly limited in complexity
-Character models are very plastic-y looking
Overall this is a fun game but it needs some serious patching for online play to be worthwhile, as a single player or 2 player experience it's a lot of fun!