As mentioned before my priest is holy spec, and currently level 77. Which means that in comparison to pre-patch 3.0.2 I have a few more new spells from the trainer or talents: Hymn of Hope, Mind Sear, Guardian Spirit, but not yet Divine Hymn, which I'll only get at 80. And looking through the new spells, I must say I'm not impressed. Maybe they do get a bit more useful in a raid setting, but for a typical leveling activity with a mix of soloing and 5-man groups they are pretty much useless.
Hymn of Hope: In a long channeling process this spell restores 8% of mana over 8 seconds, to all group members. In a solo setting this is completely useless: You don't have the time to use it in combat, and outside of combat you'd get far more mana from sitting and drinking for 8 seconds. In a group this is still not much good, because if you as the healer are out of mana, channeling for 8 seconds to get enough mana for just one or two heals isn't going to save you. The tank is probably dead before the 8 seconds are over.
Mind Sear: Another channeling spell, this one dealing AoE damage every second for 5 seconds. Unfortunately in most circumstances Holy Nova is far superior to Mind Sear. Mind Sear deals damage in a 10 yard radius around an enemy target, but does not damage the targeted enemy. So even in the best possible case you can only kill every mob except the one you target. In addition the mana per damage ratio of Mind Sear is bad, it does not have a healing component like Holy Nova, and in a group situation you will not have the "doesn't cause aggro" advantage of Holy Nova. The only thing Mind Sear will cause is to have the frost mage snicker in the background. I couldn't find any good use for this spell while soloing.
Guardian Spirit: Neat idea for an emergency button, you protect somebody from dying for 10 seconds. Very situational, and pretty much useless for soloing. If I still have mana, I can cast other forms of instant self-heals to keep myself from dying. In a group this could be useful for tanks that haven't got enough defense and suddenly drop precipitously in health. In that situation Guardian Spirit prevents them from dying from a second crit, and makes it easier to heal them back up to full. But in a well-organized group this situation shouldn't happen all that often.
I haven't really looked all that much into the new spells of other classes. Shalkis found Mirror Image to be less useful than expected. What I've seen from Warrior new abilities looks a lot more useful. How are the new spells and abilities of your class? Did priests get the short end of the stick, or are most new spells of only limited use?