I just did a relic turn in and got the same spell, so I'd like to throw in my 2 cp.
I'd like to start off by saying that I don't think the spell is terrible, and it is nice to have a high end spell to top off our elemental cloak line. With that said, I was disappointed to see this in the "relic" category.
If you are turning in a relic spell, it means that you're most likely in a raiding guild and already have some very decent gear and a good sized mana pool. I'd think that the average caster in this category would have a pool somwhere in the high 3,000's to low 4,000's. So this spell adds about 6% to their existing mana pool and adds about the same amount of resists as SoS, however it is self only. The resists are nice and the mana is great, but it still won't even buy me one more nuke in a raiding or grouping situation.
Perhaps my perception of a "relic" spell is off, but I've invisioned them not only as the epitome of a line of spells, but also as something somewhet unique and very helpful to that class. The other relics in the mage line fit this description well:
Relic: Bladewind - great new nuke, noticable dps increase, mages rejoice
Relic: Storm of Elements - great target based AE, more rejoicing
Relic: Cupola of Incineration - highly useful in raiding/grouping situations - everybody loves the mage
Relic: Manifest Elements - Mages cry tears of joy and throw a party
and...
Relic: Til's Elemental Ward - Mages blink, go check a few spell databases, scratch their heads, cast the spell, cry
Yea, the crying comes from wishing it was the relic pet or nuke instead, but the point is I don't think this lines up with the rest of the spells in usefulness or impressiveness. If you've gotta be a raiding mage to get this, make it something really useful to a raiding mage. The resists are cool and the mana is cool, but make it available to all mages. I'm sure this is even more exciting to the non-raiding mages as they will have less opportunity to max their resists and have a smaller mana pool.
I'd imagine if you poll all of the raiding mages, they won't be jumping up and down over this spell as it adds very little to their effectiveness on a raid, which is where they spend the majority of their time. It's a nice spell, I just think that it shouldn't be added to the highest tier of spells which raiding mages strive for (ok, so the one archaic spell we get is a little higher...).