I started using it to organize my wedding list, and have come to the conclusion that while it looks pretty, it is a toy app unsuitable for any remotely sophisticated spreadsheet user:

• The header row cannot be locked in place, so when you are navigating a long spreadsheet, you lose track of what column is what.
• Its function library is incapable of even basic functionality like counting the number of checked checkboxes in a range
• You cannot rename columns/rows from their default letter/number labels to more meaningful ones
• When making a bar chart for a data series that holds percentages, the axis is mislabeled – instead of showing “75%”, it will show “0.75”
• It is horrendously slow. On my dual-2GHz G5 with 5.5GB of RAM, there is a noticeable delay in producing a chart for a mere 4×2 table.
• The bundle directory document scheme (where a document is actually a directory) is neat on paper but makes transferring Numbers files more unpleasant than it need be, because you now have to zip the file prior to transfer.

The 1980s called, and they want their spreadsheet back…