(based on mail from David Alpert, sharp develop community forums & my personal thoughts){BR}

• Designer for HTML (XHTML and other standards); no reformatting of source code
• Designer for ASP.NET (server-side controls)(see the wiki page here.)
• Projects based on directory (both VS project formats should be supported)
• Code completion for asp.net, javascript and css
• Integration code behind with aspx - controls variables & stuff
• good error reporting
• files that haven't been updated to not to be deployed/published all the time
• DLL's not to be uploaded unless they have been recompiled
• based on .net 2.0 ftp support
• GUI for managing site definitions or FTP connection information (server, username, password, & remote directory). (project-independent & those saved in project solution)
• accessing files from 'project explorer' like window (double click downloads a file and opens it)
• auto upload to ftp on save
• downloading/uploading files through drag & drop
• more than one connection open at the same time
• local start iis & open page (via right click - 'view page')
• publish release build to ftp

• http://community.sharpdevelop.net/forums/thread/3361.aspx
• http://community.sharpdevelop.net/forums/thread/2428.aspx
• http://community.sharpdevelop.net/forums/p/9283/25882.aspx#25882

(Needs some posts to become complete...)

• Mieszko Lassota aka Miechu
• David Alpert
• VijayWroX
• Mansoor

• http://msdn.microsoft.com/asp.net/reference/infrastructure/wdp/default.aspx
• http://www.eworldui.net/unleashit/
• http://www.asp.net/downloads/archived/web-matrix/