It looks like it's the end of the road for Microsoft's suite of Expression design tools, as Peter Bright over at Ars Technica notes.
Expression Design 4 is being phased out entirely, though it will be patched through 2015. Expression Web 4 also is being dropped. And Expression Blend -- which made it up to Version 5 -- is being folded into Visual Studio.
Read more at source:
Microsoft phasing out its Expression design tool suite | ZDNet