Back to OP. Luckily my healing core of 4-5 people has been the same for almost 2 tiers, not including this one. However my guild personally has had a person who switched to dps and our resto druid is giving blizz one more full patch to see if they fix or can improve druid healing. Our disc priest crushes meters with atonement, second is usually myself (pally) or our holy priest and by the time our druids hots things he's already been sniped. Shamans aren't "amazing", and they're not "bad", but they could certainly be better. Atleast resto shamans bring very good utitlity with SLT, HST, MTT, good tank healing.
I wouldn't say healing is necessarily bad or boring this xpac but I think certain classes are making it not fun or atleast uncompetitive for some. Right now I think dps classes have changed so much since cataclysm that people are changing to try them out or falling in love with a dps spec that was boring before MoP.