Software sites should be based around the software, informing you of everything you should know.

• The simple description of the software on the main page
  
• A section for documentation
  
• Link to the source code and links to binary releases for specific distro
  
• A clear changelog and important news or changes on the front page (as in critical things)
  
• A contact link or bug report page.
  
• A how-to-get-it-running page.
  

http://i3wm.org/ and http://www.irssi.org/ have satisfying webpages.

This topic is under-rated and under-discussed.

EDIT: I dislike http://ratox.2f30.org/.
http://msmtp.sourceforge.net/ is simple and clear even though the design is not very appealing.