It's great that shields will allow some absorption, but it sounds too much like a passive quality in shields themselves as opposed to actively blocking them. And what I want is to actively block them. Sounds more like they just added a new attribute to shields, "absorbs 10% magic damage" as opposed to clicking your block button and having that fireball impact the shield. Just saying.
That was my beef with enchanted shields in Oblivion as they jsut gave you a constant effect resist or reflect or whatever.
What i'd like is that for regular shields to be able to block magic when you held down the block button, this at least lends a bit of interaction and immersion in the whole process. . Obviously the amount blocked depends on the shield and the magic.
eg a wooden shield will reduce the effect of a fireball, even a strong one though it might get destroyed in the process. This represents the shield absorbing the impact at a cost to itself rather than the wielder getting the full force. = Afterall in real life a shield is more like ablative armour, some thing to take a big hit and be discarded as necessary
as for area of effect spells. i think this is a case for tower shields that you can hide behind almost entirely. obviously something like a buckler would give almost 0 protection against AoE effects like dragon fire.
eg, in the game play video where we see the Dovakhiin stand up after the dragon fire attack (just before he unleashes the dragon shout) it looks like he should have emerged from behind a large shield but in the video he has none so it just looked like he was fire resistant which i thought a bit odd. Anyway, a large shield, even a wooden one would've protected him well enough from that sort of attack. (a plank of wood in real life doesn't actually catch fire that easily more so if its treated properly. Only if its exposed for a long time to an open flame, thats why its very hard to start a camp fire without tinder. So a large hefty wooden shield should be useful protection even tho it might get singed)
metal shields will obvously afford more protection.
elemental effects like electricity and heat melting the shield would be cool, but not something i think they would implement.