I moved from DNN 4.0.3 to DNN 4.4 and noticed that there are significant web.config changes (actually as a part of 4.3 Membership Services Provider Abstraction ).
However I didn't find any clear documentation about Web.Config changes.
From my understanding the folowing changes happened:
1. Microsoft ASP.NET membership defaultProvider changed from "DNNSQLMembershipProvider" to standard MS AspNetSqlMembershipProvider -System.Web.Security.SqlMembershipProvider.
2.roleManager and profile providers sections were deleted from system.web section of web.config.
3. New sections "members","roles","profiles" were added to "dotnetnuke" sectionGroup