There has been a lot of speculation on this. Some say Q1/Q2 of 2010, some say summer, others fall. I fall into the latter camp - I think fall/winter 2010, likely in the October timeframe. Why? Well, because over the development of World of Warcraft, Blizzard has been focusing on a more consistent release cycle. The following table illustrats that (the designation of major/minor is based on my view of the patch as I experienced it):
Patch Date Type Content
1.1.0 7-Nov-04 Major Initial Release
1.2.0 18-Dec-04 Minor Marudon added
1.3.0 7-Mar-05 Major Dire Maul added; outdoor bosses added
1.4.0 8-Apr-05 Minor Honor added
1.5.0 7-Jun-05 Major Battlegrounds
1.6.0 12-Jul-05 Major BWL Added
1.7.0 13-Sep-05 Major ZG added; AB added
1.8.0 10-Oct-05 Minor Silithus finished; 4 Dream dragons added
1.9.0 3-Jan-06 Major AQ added; Silithus CC quest hub;
new Tier 2 models; timbermaw hold
1.10.0 28-Mar-06 Minor Weather; Tier 0.5 added
1.11.0 20-Jun-06 Major Naxxramas v1.0
1.12.0 22-Aug-06 Minor Cross-realm BGs; outdoor pvp
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2.0.1 5-Dec-06 Major TBC content patch
2.1.0 22-May-07 Major Black Temple added; new quest hubs; druid
epic flight; new arena
2.2.0 25-Sep-07 Minor Voice Chat
2.3.0 13-Nov-07 Major Zul'Aman; Guild Banks; level 20-60 revamp
2.4.0 25-Mar-08 Major Sunwell and Isle of Quel'Danas;
new instances and quest hub;
new badge gear
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3.0.2 14-Oct-08 Major WotLK Content Patch
3.1.0 14-Apr-09 Major Ulduar opened; Argent tournament;
Dual Talents
3.2.0 4-Aug-09 Major Crusader's Coliseum; new dailies; new BG
3.2.2 22-Sept-09 Minor Onyxia returns; minor talent tweaks
3.3 PTR 01-Oct-09 Major Icecrown Citadel
During the 1.x development cycle, patches were initially pushed out at about one per month. As the game matured, however, that slowed down to one patch per 2-3 months, and then beginning in 2006, it became 5-6 months between major patches.
In the 2.x development cycle, it was roughly 5-6 months between major patches. And this appears to be the case in the 3.x development cycle, with the exception of 3.2 coming about 4 months after 3.1.
Anyone who works in software development knows that the biggest hurdle to overcome is release predictability. As WoW has matured, Blizzard has gotten better and better about knowing what they can fit into their release cycle, and this is evidenced by the fairly consistent rate at which major patches are released.
Obviously, this is just my opinion and is pure speculation, but here's what I see happening:
3.3.0 will likely drop after the new year, probably in late January or early February. They will likely do an incremental release of bosses to avoid guilds from rushing through the content. IC will have 12 bosses, but I don't think all 12 will be available from the start, nor do I think they'll limit it to one per week. IC is supposed to have 4 levels. I see each level being release separately.
This means that IC won't be *fully* available until the beginning of March. They'll start the Cataclysm beta in April/May, and beta for roughly 4 months (wotlk beta was about 4 months), making the release sometime in September or October.