Yeah, I found a chart that lists the speed comparisons for various cards on various bodies. For the 7D a 20 second burst yields 66 images with the 90MB/s card and 62 with the 60MB/s card. Not a big enough difference to merit spending an extra $50 for the faster card.
Adorama has a One-Day-Sale every day this week for different SanDisk card types. I'll be waiting until the 60MB/s cards go on sale Wednesday.