More of an opinion then anything else but what do you feel is more important, haste rating of spellpower? Obviously a good balance would be preferable but a lot of the Northrend quest rewards give you an option between spellpower and improved haste rating. I find the haste rating super useful in ripping out quick heals. The quick heals in conjunction with a high critical change is great but if you have a higher spellpower your heals should be better anyway, right?
Again, more of an opinion from da' peeps here.