Right now the following items are for sale:
3. Cosmetic Items (helms and whatnot)
In the near future there will also be for sale:
3. Level Boosts
------------------------------------------------->What we see here is the adoption by Blizzard of the successful business models of Private WoW Servers.
The following items are also sold in Private WoW servers:
Mod-note: I will take a note right here for you, there is no real line of any sort between Live (Actual) servers, and private servers. - Gehco
a. Raid Tier Armor
b. Raid Weapons
c. PvP armor
d. PvP weapons
e. Cosmetic Armor Sets (past tiers and popular xmogs)
It is only a matter of time before we see the above items also sold at the WoW shop IMO.
Blizzard fanbois will still tell you that the above does not constitute P2W: Strictly speaking, you do not need to buy any of the above items to win the game or progress your character. You are free to follow the normal progress path to acquire any and all of the above, therefore, even if Blizzard sold all of the above just like successful private servers do, their game would technically still NOT be P2W.
Now, I do think that Blizzard is losing tons of money by not making available for sale Raid Tier Sets/Weapons and PvP tier sets and weapons. There are hundreds of thousands of rabid WoW fanbois who would gladly pay any amount of money to get their 10 toons per server (across multiple servers) boosted and fully decked in the best PvE and PvP and Cosmetic armor possible.
We are speaking here about millions of $ of lost revenue.
Ofc, the above decisions would be unpopular with some forumies, but still the rabid fanbois would buy regardless.
Since Blizzard is a for-profit company and all that, it is only a matter of time before someone who's greedy from within Blizzard convinces the others to put the above in motion, and the older the game gets, the more in-game items will be put for sale.