as some have said, these games are all DX9 games with DX10 patched on.
I read a lot of this on the CoH forums about their DX10 patch, and the summary was this:
Microsoft offer a codepath to translate DX9 code to DX10. This saves time over writing native DX10 code for everything.
Problem is, its SLOOOOOOW. These companies dont want to spend a lot of time and money re-writing their entire graphics engine for DX10, so they throw it through the microsoft meatgrinder, patch up the holes and end up with what we know as DX10 games.
Games need to be made for DX10 from the start, with DX9 coming later with a simplified version of the engine - NOT crappy additions like CoH had with flowers and debris...
Seriously: Who here would NOT have been happy with DX10 merely providing better FPS with the same level of graphics? Imagine if crysis DX10 had a 30% FPS boost, instead of a 300% hit?