PowerPivot 2010 - EXCELLENT Excel 2010 add-in
At work and home, I use Office 2010 extensively and it's the most well designed and capable version I've used so far. While many of the components I use extensively like Excel and Word are similar to their Office 2007 counterparts, the User Interface is much more intuitive in the latest version.
The capability to create Pivot table views is greatly improved in Excel 2010, as it's more naturally built into Excel. In building sophisticated spreadsheets, Microsoft also offers an Excel plug-in called PowerPivot 2010 that can work with huge data bases exceeding even the million line row limitations of Excel. While I prefer using Access for these types of queries, PowerPivot allows you to stay within tool to create summary views.
PowerPivot 2010 - Great writeup on value of processing large external data bases
QUOTE: Microsoft’s PowerPivot add-in for its forthcoming Excel 2010 spreadsheet enables users to work with much larger sets of data than is possible with Excel alone. Microsoft’s PowerPivot is an add-in for the company’s forthcoming Excel 2010 spreadsheet application, which first grabbed my attention by the way it enables users to work with much larger sets of data than is possible with Excel alone. For instance, I used PowerPivot to load and browse through a data set that ran 3.9 million rows—about four times Excel’s existing upper limit—and I had no more trouble scrolling around in the set than I would with a spreadsheet of only several hundred rows.