I upgraded the operating system on my Macbook to Lion yesterday (or 10.7 if you prefer numbers). It was fairly painless and cheap, being done all online, i just had a 3+ GB download to do first. There are apparently over 250 new features i can now play with.
Many of these new features i am not that interested in though such as Launchpad (Applications from the menu does the same thing already) but the overall look and feel of Lion is nice and it seems to run pretty swiftly too. I have yet to take advantage of some of the more interesting new features like Auto Save and revisions but hopefully my apps will catch up with the OS.
I think this will be an upgrade that will take some time to be fully appreciated but i'll let y'all know if i have any problems or otherwise.