• Lorwyn
• Morningtide
• Shadowmoor
• Eventide
• Shards of Alara
• Conflux
• Alara Reborn
• Zendikar
• Worldwake
• Rise of the Eldrazi
• Scars of Mirrodin
• Set 2 of the Scars block
• M10
• M11

Obviously Faeries will be a major power in this format, with Scapeshift, Scapeshift Zoo, and Traditional Zoo close behind.  Reveillark control decks (not combo style, sorry, Body Double!) will be big, and people will get to dust off their playsets of Figure of Destiny and Reflecting Pools.  Vivid manabases will be the norm for the next season and any deck that can efficiently attack that manabase (Spread 'Em with Fulminator Mage?) or battle back with extreme consistency in its mana (Kithkin, Faeries and dedicated burn decks) will have to be good enough to overcome the sheer card quality of the 5CC Control and Cascade decks.

There are definitely upsides and downsides to the new Extended format.  I wish there was something in-between, like the rumored OverExtended format (Mercadian Masques and up) or something more like classic Extended, which rotated sets out every two years and gave some cards (dual lands, anyone?) special dispensation.  I just feel that the new Extended is far too close to Standard, and the room for innovation isn't really there - much like Standard used to be the best block decks against one another until Wizards did a better job of making block themes interact, the new Extended may turn into the best Standard decks from the past three years battling against one another.  We'll see how it goes, but I really hope the next announcement from WotC is a new format (and not one that involves four booster packs and 30 card decks).