1. They've changed the lv cap from 100 to 172 (or 221 if you are a member).
2. They've added almost double the sector levels
3. You can set your room to medium and hard difficulty, which give 1.5 and 2 times the exp respectively.
4. Lots of new items, such as leech skill, and some sweet new trans packs
5. You don't have to pay for coins anymore. You earn them by playing sector (granted, it'll take a while to get enough to buy something big, but it's still better than paying real money ^^)
6. New Zylon shop, with items that are very kick ass, but do require that you pay real money
7. Membership, with several benefits including double exp, and access to elite items
8. Survival mode in sector with unique survival maps. You have to use the room tag "{s}" to see these maps
9. LOTS of new room tags for PvP, this adding loads of variations to PvP gameplay
Plenty of other new features too, but these are some of te most noteable...