This is pure speculation by a site called Random Battle. Take it with a grain of salt (or a lot of salt). Regardless.. there's many points that makes a lot of sense after having read this article.
Almost all of the estimates I’ve heard for Wrath of the Lich King’s release put it at Q3/Q4 (Autumn) of this year, but I’m not entirely convinced. Patch 2.4, due out in the next few weeks sometime, has a bunch of really interesting changes for the game. Most notably, the inclusion of a new 25-man dungeon and some major changes to how easy it is to obtain epic-level PvP gear. Hmm. That sounds awfully familiar. Where have I seen something like this before?
Oh, wait. It’s kind of like what happened in Fall of 2006, when Blizzard gave players about one month with Naxxramas (the new 40-man at the time) and made the best PvP gear of that period ridiculously easy to get your hands on, before making it all pointless and wiping the slate clean with the release of The Burning Crusade. Is it possible that we’ll see a late-Spring stealth Wrath of the Lich King release? I’m sure Blizzard has learned more than a few lessons from their first expansion launch (players weren’t thrilled at how little time they had to explore Naxx before it became obsolete), but giving players 2-3 months with the new patch should be just enough time to let the serious raiders master Sunwell and let the more casual players frolic in their cheaply-obtained epic loot before a gear wipe resets everything again.
Head over to Random Battle here to read the full article.