I would like to weigh in here too.

I finally got my rigs operational. Still need to install UIs, finish a few more things, etc but I made some test accounts and walked around from the tauren starting area to TB. Started and stopped follow, went up the lift in TB, noticed the "walk to you" speed and basically tested it to see if I could DC it.

Keep in mind that this is with a FRESH install of XP, FRESH install of WoW (no UI mods) and redundant, load balanced internet.

I had exactly 0 disconnects. Which is a surprise actually.

I will of course keep testing it but so far it is smooth as silk. Perhaps the latest patch ninja fixed it - but I would suggest the WTF folder deletion option. Also, try stripping your UI if all else fails and rebuild it.