Yep, Valve has been doing that for a while.
I think the developer/publisher can change pricing for separate regions, but the default is 1$ = 1€ = 1£.

See the age old 1€ ≠ 1$ thread: http://forums.steampowered.com/forums/showthread.php?t=770231
Related: http://www.steamprices.com/eu/topripoffs