Recently I went through the pretty painless procedure of upgrading my Macbook to OSX Lion from Snow Leopard. After spending some time re-configuring it was almost back to how it was. But it was far slower than before.

Getting used to Natural Scrolling didn't take very long, apart from when using a scrolling mouse - that certainly took some time. But now it seems second nature, and going back to windows seems a little odd sometimes.

Sadly it erased some of my settings, which took me some time to discover, locate, and change back again. Other than that there weren't seemingly too many changes.

The slowing seemed extreme. 3x longer boot times and far longer shutdown times than I'd had before. So I tried rebooting in Safe Mode (holding shift), which I've read does some rebuilding for speed. No joy. Next I tried repairing disk permissions using Disk Utility, the difference was fairly minimal (and quickly reverted itself again). So after nosing around on the internet I found the solution for me.

Holding down option (alt) whilst booting allows you to select which disk to boot from, the non-default one of these provides Disk Utility again, but this time allows you to repair the disk, rather than just disk permissions. After doing this I enjoyed faster boot times than before, but still a little longer shutting down occasionally.

Very nice user experience, with some fluff which is easier to revert to be more like Snow Leopard.