I'll be the one doing the review TFO
In short:
The game plays like what Diablo would play like if it was a MMORPG. No crafting, no messing about, just combat and missions. It's grouping and guilding systems are good (you can have a secondary Superhero group colour scheme that everyone changes into when going on a grouped mission, which is nice). There are 5 classes - melee defence, melee damage, ranged, wizard and cleric. At start you choose 2 power sets - i, for example, chose Tanker with Super strength and invulnerability (Ie, Hulk). You also choose your origin (Science, Magic, Natural, Mutation, Technology) which mainly affects what enemies you fight the most. At levels 6, 8, 10 and 12 you can chose an addition power set (i chose Teleportation at 6). You can get up to 6 power sets in total, which include stuff like Fire damage, stone skin, flight, jumping, medecine, etc. Each set has 4 (for after-creation sets like medecine, flight and teleport) to 8/10 for during-creation sets (any armour or damage dealing, which cannot be chosen after creation).
The city itself is really nice - it feels real. Though the mobs (muggers etc) are wierd - the crime rate in this place is closer to civil war than anything else.