I am trying to connect my project from VS2010 to expression 4, but it is not so intuitive. So I'm asking myself if VS2010 has the same capabilities as expression 4?
What is the best solution for a programmer like me that writes css3, html5 and javascript that needs to work together with c# and asp programmers?
Expression and Visual Studio have a very different focus group. Expression is for designers and has extra tools/capabilities to better handle creating your markup. Visual Studio is more geared towards hooking that design up with code.
That isn't to say you can't build a beautiful site with VS alone; many do it. However, if you need good tool support, as opposed to hand coding the look, then go with Expression.
Expression does support the project models handled by Visual Studio and has hooks to source control like TFS, so you can use both side by side just fine.
