Love the new avatar Ninapants!
So far I am enjoying Leopard. I have a few minor issues with it, and suspect they will quickly go away. x11 is broken, an issue if you're an X developer or a hard core X user. (If you don't know what that means, you probably don't need to worry.) Also there were some issues syncing iCal and the iPhone, though I found a brute force method that worked.
That said, I love Leopard. Once I figured out how to do a few things, the installation was easy and trouble free. I lost no data.
I can connect to work, including both Linux lab machines and Windows machines. It would be no good if I can't do the things I need to do. I can, and it is good.
Spaces is excellent, allowing you to have multiple virtual desktops. They did it right from what I can see. I now have AOL Radio. While not directly Leopard related, I like listening to XM Radio. I couldn't do it well on my Mac under Tiger. Now with the new Beta AOL Radio app, I can do it. What good is an OS if it can't support the things you want or need to do? On my dock I have stacks for certain groups of applications. My dock has become uncluttered.
Was it worth it? Yes. Was it hassle free? No, but then once I looked at how things are done in the Mac world, it was easy. Problems notwithstanding, I like Leopard better than Tiger, and I liked Tiger very much.