Unsurprisingly, NVIDIA is releasing another version of its unified driver package alongside the shiny new GTX 580. There are no specific performance improvements in version 262.99, but a few of the individual component are getting an update to the latest versions.
The only major changes listed are to the PhysX System Software, which will be updated to version 9.10.0514, and the HD audio driver, which will be updated to version 126.96.36.199.
If you haven't been keeping up to date with previous 260-series drivers, you'll also get the benefit of a refined installer that allows for better customisation, an updated control panel and improved support for multi-monitor and 3D set-ups.
Interestingly, a few features have also been removed. Surround gaming using three GTX 200-series cards in SLI won't be possible any more and Hybrid SLI using an integrated GPU is no longer supported. These are pretty niche features, though, so shouldn't affect too many people.
As for changes, that's about it - other than GTX 580 support, obviously. If you have one of NVIDIA's monstrous new video-cards, go ahead and grab these drivers straight away from the download page. Otherwise, you'll probably be safe saving the bandwidth and holding off until the next major release.
For more details, the full release-notes are also available (PDF).