PvP sets will be even cheaper in the expansion

Apparently PvP sets will be even cheaper in the expansion. While the stated reason is that expansion items are so much superior that PvP sets should not take so much effort to get, I wonder whether there are other reasons as well.

Anyway, since the PvP sets are now the Blizzard-sanctioned way to go to gear yourself up for the Expansion, I think that all level 60 PvE content before Naxxramas will be mothballed.

I'm still wondering about the difficulty level of Burning Crusade instances. The expansion was obviously tested with well-geared characters, so a fresh level 60 character might want to grind some honor before stepping through the Dark Portal.

All in all, this makes gear progression quite interesting. My guess is that the most cost-efficient way to gear up your character from scratch would be to do PvE for the low- and midlevels, and then start PvPing heavily when you get closer to 60. When you have enough PvP gear, you go to Outlands and gear up solely on PvE until level 70, where you start the Arena battles and get your tier 4. Raiders will go up one more notch and farm Illidan, Magtheridon, Kael'thas, Lady Vashj and Archimonde for their tier 5, though.