Visual Studio 201 Ultimate vs Professional

Dear,
Can any one tell me what is difference between visual studio 2010 ultimate and professional version.
Actually i have already installed ultimate version but now i got confused that whether it contains all features of visual studio 2010 professional version or not?
Some websites are telling that it is for developers team but i have one concern only that is it sure that ultimate version contains all features of professional version so we can do every thing in it what is possible in professional version?

thanks