Speck HD wrap fits iPad 3
Not my favorite case, but it works wonders for people like me who carry the damn thing all over the place and put it under the car seat on occasion and want the screen and back protected.
Yes I thought it was not possible considering how it fits the iPad 2, but my 1-year old case made a very tight fit and works fine on the iPad 3. It seems to fit on the iPad just fine, but inserting the iPad into the case was the difficult part.
If you have a brand-new case, good luck wedging it in there.