We have Sharepoint at work. We are trying to use it for our intranet. The decision to go for Sharepoint was probably made by some managers after a long and taxing lunchbreak with some Microsoft representatives.
Tips for Enhancing the Accessibility of SharePoint Web Sites
Here's some choice quotes:
To modify the alternative text used for the Image Web Part on the Home page by replacing the Image Web Part with a Content Editor Web Part
which basically says: ok, our image thingy you can use to quickly put an image on a page is fucked up so bad we recommend using another method entirely.
To add a Skip-to-Main content link (for example, in an AllItems.aspx page)
#1. Create a blank one-pixel image file named onepixel.gif...
Please don't make me go on.