I made use of the new RealID cross-realm grouping to run a few dungeons with my son last night, who is a different server than I am. He wanted to do some leveling, and had some toons around 60-ish, so I dusted off my old Night Elf warrior, Tempus, and tanked a few. I had to re-do all my talents and buy some glyphs, but our tank/healer combo got us instant queues, and we burned through everything at a very fast pace.