Leopard impressions (a.k.a. Mac OS X 10.5)

I didn't purchase Leopard straight away - I waited for couple of months to see if there are any major issues with it. Since Apple has released update (10.5.1), most of the initial issues that users were complaining about seem to be resolved.

For my productivity, I found Finder improvements to be of great value. Viewing various file types with the press of a space bar is fantastic. Viewing PDF's and movies is great too. Options that let you customise the way you view your files on desktop or within Finder window makes it a much better option for users with larger screens.
Another big feature for me is Spaces. No more clutter on my desktop, every application is organised in separate virtual screens and switching between screens is a snap. This feature belongs to one of those that makes you wonder "how couls I do my work without it..."

I also like Stacks, which I found useful, as well as Downloads folder, as I frequently download work PDF's and documents. Stacks and Finder improvements allowed me to part away with applications such as Overflow and Path Finder.
Mail application has some really good improvements. Tighter integration with iCal is a welcome development, as well as the inclusion of Notes and ToDo entries. RSS feed is also included, as well as solid junk mail filter.

Preview application is one of the "sleeper" hits within Leopard. Viewing PDF's is a better experience, as it gives us options to modify views, view bookmarks and annotations... viewing images is also good, and there are some handy tools thrown in as well. Rotate image, selection, save images in a variety of formats etc. I heavily rely on "Adjust Size" tool, as I no longer need to import pictures into iPhoto to do this. Nice.

My kids absolutely love the much improved Photo Booth application. Some of the new effects are quite good, multiple shots option is great, while feature where you can have a moving backgorund behind your face doesn't always work as advertised.

Overall, Leopard is a worthy update to an already great operating system (Tiger). With a few more updates, Leopard is certainly shaping up to be a good choice for home and small business users.