For those of you who have dual spec and are mana users, you've noticed that mana is reset to 0 when u respec. If you're on a battlegroup with very short (or instant) que times for BG's u can just hop in que (being able to que anywhere now) and just afk out and you'll have full mana!
Being on a very busy battlegroup myself this my perferred mana regen option since drinking takes forever. Only downside is you'll be flagged for 5mins.
twocents