I have been taking a look at Google Docs and Spreadsheets. However, my default browser is Safari. Apparently, Google doesn't insert the "Open as Google spreadsheet" link alongside a spreadsheet attachment when viewing gMail in a Safari browser.
Now, I can live with that limitation in Safari. I am sure it will get fixed in due time. However, I typically use Apple's Mail.app to read my gMail. It struck me that Google is missing a viral trick in promoting their Docs and Spreadsheet product.
Why doesn't Google insert the "Open in Google Docs" link in mail that is downloaded? I would certainly appreciate this feature when reading gMail on my iPhone. It would be a really cool feature to be able to click on the link and load my Docs and Spreadsheet profile and be able to browse the attachment. Since iPhone doesn't support PowerPoint files this would be a great additional feature.
This feature can't be too difficult to implement. it requires Google to pass the file from gMail to Docs and Spreadsheets - but that can already be done.
The impact of this additional link in email provides the equivalent of an invite to Google Docs and Spreadsheet with every word, excel and powerpoint attachment emailed via gMail. That could be an extremely powerful viral promotion of Google Applications.
Update: Check out the new forms feature in Google Spreadsheets. This makes the collection of data from multiple recipients so much easier to accomplish. I would like to see some refinements, such as the ability to capture the email address of the person entering the data, and the ability to provide a named range as the source for lists to select from but this is a great first step.