js spreadsheet (2)
Maybe you will find it useful.
The best way to deal with tabular data with jquery is probably using Slickgrid
I did a plugin for copy/paste from/to excel: http://labs.nereo.com/SlickGrid/examples/example-excel-compatible-spreadsheet.html
The plugin has now many bugs fixed and features added by the community (eg. undo/redo support) : https://github.com/Celebio/SlickGrid/commits/master