Boomkins provide like 5 buffs to the raid. Paw, 13 percent bonus spell damage, 5 percent spell crit, 3 percent haste, 3 percent hit (well, provided you took the talent). Granted, most of those buffs are also provided by other classes, but very few classes provide the amount of raid wide buffs. In a 25 man your buffs will likely be provided by others, but in 10 mans they can fill in a lot of gaps. Not to mention good DPS and ulitity like combat rez and innervate, the latter of which is more useful than it was already.
It is, however as mentioned, a class you dont see stacked too much. But if you're a good moonkin, chances are you'll bring enough DPS to be added purely for that rather than the buffs.
Edited, May 27th 2009 6:41pm by Sinizine