SharePoint as a collaborative alternative to wikis is the point of Oliver Rist's recent Infoworld column. It seems to me SharePoint is far more preferable for team projects because it can do much more than your average wiki. I don't even think it's a fair comparison.
SharePoint will be integrated into Microsoft Office 2007, so I expect it will become almost as commonplace as Word or Excel. The use of SharePoint should explode next year since it is such an easy to use (and manage) collaboration tool.
tags: libraries, librarians, SharePoint, wiki