I purchased Microsoft Office Home & Student 2010 primarily to get the latest version of Excel. I think Excel is one of the finest programs ever written. I use Excel at my office and needed a copy to use when I work at home. I like Word, too. It is also a fine program. But Excel is incredible. I consider myself an advanced Excel user and appreciate it's power. I highly recommend this version of Office 2010. The installation was easy, but took a fair amount of time (like maybe 45 minutes). Excel Rocks!

This is a huge improvement over Office 2003, in my opinion. Not a whole lot different than 2007 though. I initially had some trouble adjusting to the different layout, with the "ribbon" on top. But the more I've used it, the more I've come to like having everything readily available without having to click through the annoying "File, Edit, etc" menus.
It is a far better experience that google documents. Night and day, and easily worth the money.