Same for me : F3 (Expose) and F4 (Dashboard) don't work.
Called Apple twice (in France).
1. A first stupid told me : wait for the update. Told her I already had downloaded and installed it.
Stupid added : There is a new update coming up on Monday 13 august (I called Friday 10).
Told her I did not believe Apple would launch Updates every two days…

2. Called again today. A second stupid asked me the same about Update 1.1, then consulted his top technicians keeping me waiting for TWENTY-SIX MINUTES before asking me THREE times if I had downloaded Update 1.1, and again to wait for the new update. As I was pretty upset with so much stupidity, he told me to call back tomorrow.

3. Usually, Apple support is way above other supports which famously suck like HP (Mamma mia, the worst of all) or Micro$oft. I wish Apple would NOT follow suit…