You can use Office 2010 web apps FREE from a SkyDrive account and openly collaborate with people or you can pay $20 a month per seat for Office 365 and you will get Sharepoint and ALL Office 2010 desktop apps.
The office web apps work perfectly in all browsers (I've tried Chrome, Firefox and IE).
Considering the cost of playing around with Google spreadsheet with those restrictions, it's possibly a good idea.