Microsoft today announced an update to their official stance regarding supported browsers for SharePoint 2010:
Unless otherwise stated, all browser versions are supported. Period.
That’s some change in approach. Previously you had to keep track of a matrix of the different versions of each different browser.
However, it’s important to note that supported does not mean all browsers react the same to SharePoint. Visually, some elements of the UI can behave differently and from a security standpoint, you may receive multiple login prompts when using a non-IE browser. Some features may not work (e.g. opening a document library in Windows Explorer – works in IE but not in Firefox). It’s an important consideration, particularly as part of standard user training if you have multiple browsers in use at your organisation.
The official statement on TechNet makes this clear (emphasis mine):
SharePoint Server 2010 supports several commonly used Web browsers. However, certain Web browsers might cause some SharePoint Server 2010 functionality to be downgraded, limited, or available only through alternative steps. In some cases, functionality might be unavailable for noncritical administrative tasks.
As part of planning your deployment of SharePoint Server 2010, we recommend that you review the browsers used in your organization to ensure optimal performance with SharePoint Server 2010.
Also, it’s important to note that for non-IE browsers, only the latest publicly released version is supported. Organisations that are only just shifting away from IE 6 (take note, HMRC) need to be snappier in future about upgrading to stay within support boundaries.