Time Machine is the one feature in Leopard that I am both most excited about, and dreading. It is a fantastic idea to have the OS take care of backups automatically, and I think it will solve many common problems folks have. However, as Anil Dash points out, Microsoft did this first. Microsoft's feature is called Shadow Copy, and it just isn't as sexy as Time Machine, though it does pretty much the same thing. Anil opines that whilst it is true that Microsoft did this first Apple will get all the credit because Time Machine is so dang cool.
Which brings me to why I am dreading Time Machine. I've said this before, but the jarring nature of Time Machine's interface concerns me. There is nothing like it on the Mac, and I am hoping that Time Machine doesn't herald the arrival of all sorts of wacky, non-standard UI treatments. Oh well, at least my files will be safe.