Danny Sullivan has all the details on Google Spreadsheets To Launch Shortly. Don't believe me that Google is creating a Web based Excel-like application? Go to http://www.google.com/googlespreadsheets/try_out.html or check out the Google Spreadsheets Privacy Policy or the Google Spreadsheets Help Center. It should be live some time today at http://spreadsheets.google.com/.
There are more screen captures at the tour which is available.
Forums are discussing it, but it is not getting as much buzz as I thought it might. Of course we have the debate if this is way too off search related focus and how much this may tick-off Bill Gates. Oh, let's not forget how much this may upset those small companies that have been designing web based alternatives to Excel for years, more on that at Resource Shelf.
Forum discussion at Search Engine Watch Forums, WebmasterWorld I and WebmasterWorld II and DigitalPoint Forums.