Personally, I don't mind high octane special effects driven films, they can be a relief from having to think too much about what you're watching.
However 2012 takes this to the point of ridicule. You would expect a hollywood blockbuster like this to have one or two 'skin of your teeth' escapes, but here the movie seems to be unable to go 10 minutes without the ground falling out from under the protagonists' car as they drive through (yes, through) a falling sky scraper, only to survive and then have their plane narrowly missed by a volcanic eruption and make it through a pyroclastic flow, etc. etc. etc.
All in all, far too unrealistic and far fetched to make even a child suspend their belief for more than half an hour, I kept watching in the hope it would redeem itself, but alas no. Some battling performances with a dire script manage to drag this up from 1* territory.