Alliance RP? Alive and well!
Happily I can say it's true.
I started playing here 2 weeks ago, originally horde and was distraught to find that there's no RP. I decided to give Alliance a try and originally found only 3 players in the RP-OOC channel. One of which informed me that RP was dead, the RP guild was dead and there was no point in trying. Fortunately the other 2 players were much more realistic; they said that the numbers have declined and all of the officers of the RP guild haven't been logging on (making it impossible to currently join the guild) but that there are still a dedicated few.
I gave it a week before I rerolled Alliance (one week ago) and was very happy to see there's around 10 players whom are active, almost every day. That doesn't mean they're RPing every day but I can confidently say that after having my character for only a week I've already had several RP sessions with various members, starting a quest to northern Redridge to exterminate orcs (RP quest ofc) and just happily attended a winterveil ball in darnassus.
If you want to RP Alliance is still the best choice. Join RP-OOC and download the addon Total Roleplay 2 version 1008 and we hope to see you there.
A final note: There's talk of making a casual Horde RP guild so if you're interested keep an eye on the RP section of the forum.