Since the update, in fact, I'm growing pretty disappointed with Lion. It never roared just like the good ole Snow Leopard. The Lion cub has only shyly purred and whined, so far.
One of the things that bothers me most is Spotlight performance. Assuming you noticed it, have you ever wondered what the mdworker process is doing when it jeopardizes your Mac resources? I have: staring impotently at the screen, listening to the spinning rust crackling, powerlessly witnessing how the operating system is waiting to complete who-knows-what.
This morning, I opened Lightroom, started importing some RAW files, and started working on them. Well, trying to work on them while Lion was performing its... "housekeeping".
Frustrated, I expressed my anger on Google+. A friend of mine, Joaquin, pointed out both the cause and a workaround of the new Lion's behaviour.
It turns out that Lion is performing periodic local backups
If you, like me, feel like turning off this amazing feature you can use the following command:
$ sudo tmutil disablelocal
Should you change your mind about it, you can always turn it on again using:
$ sudo tmutil enablelocal
These are just the kind of options that should be accessible in the user interface.
Hope this helps you.