Michal Pisarek says SharePoint Team Sites, out of the box, are a bad idea:
The good old Team Site is a staple of any SharePoint implementation. Whether on SharePoint 2010, 2007 or 2003 the Team Site is commonly used as a catch all site to encourage ‘collaboration’.
Therein lies the problem. For the normal user the word ‘collaboration’ has as much meaning as the word ‘Team Site’. Collaboration, as pointed out by luminaries such as Paul Culmsee, is a means to an end. You don’t collaborate for the sake of collaboration, you collaborate to solve a business process, issue or provide some tangible outcome.
The same applies for Team Sites.
A very good article by Michal that really exemplifies his experience both as an award-winning SharePoint MVP and someone more focused on delivering business value with SharePoint instead of simply meeting technical requirements. There's some great comments too.
If you're involved with SharePoint and haven't yet subscribed to Michal's site (SharePoint Analyst HQ), go and do so!