Additionally, as can be seen in the video, freezing rows and columns is much easier and the art of constructing a formula has been greatly improved through the deployment of an experimental feature called “formula highlighting." Now, when assembling a formula that references other cells or ranges in a spreadsheet, matching colors are applied to each reference (in the formula) and the border of the cell or range it applies to. This feature is harder to describe than to see (be sure to check out the video).
Google Spreadhsheets also received a performance boost in its scrolling ability through large spreadsheets. As Ho describes it in the video, users on the old version of Google Spreadsheets would sometimes notice what he called the blue screen of slowness. This is where attempts to scroll large numbers of rows at a time resulted in a blank blue screen while the browser, the network, and the back end of Google Spreadsheets caught up. This typically doesn't happen with desktop spreadsheets. In the video, Ho shows what the blue screen of slowness looks like in the old version and then how the lag time was eliminated in the new version.
One other little bit of icing on the cake that Ho says users asked for: autocomplete. The old version didn't have it. The new version does. You can see it, too, in action in the video below.