As noted on the World of Warcraft Website, a new version 4.2.2 patch is now live on all realms for Blizzard's MMORPG. Here are the fairly brief patch notes:

Dungeons & Raids

• Firelands
• The visibility of Ragnaros' Dreadflame ability has been increased.
• The size of Ragnaros' hit box during the final phase of the Heroic encounter has been increased.

User Interface

• Raid Frames should now remember whether they were shown or hidden upon subsequent logins

Technical

• Players using multiple accounts should now be available to be invited to a Real ID Party.
• Updating a raid roster while in combat should no longer cause a client crash.
• Attempts to purchase Arena Season 10 items should no longer sometimes cause a client crash. (Korea Only)