Comment 28 for bug 297543

Summing up, 173 and 177 don't work with Compiz, so there's no official way to enable the desktop effects on Intrepid if you own an Nvidia card. Now they have released a new driver which happens to be labeled as beta, but it fixes all major bugs that we're complaining about. Just add 180 to the driver list and leave 177 the recommended one. Once 180 goes final, recommend this release in the list. If possible, this should be done ASAP for the reasons mentioned above. Just my 2 cents.