Valve gotta be the best, No other developer gives free games(Portal and Alien Swarm), and countless DLCs, updates and maps for their games(TF2, L4D and L4D2).
Even CS:source and Half life 2 and episodes were updates and improved just recently despite them being released so long ago.
Also, they give the community the best modding tools and continuous support.
NO OTHER DEV does this! They all just suck your money! Valve once offered L4D2 for 10$ and tf2 for 2.5$!! Activision charges players 15$ for 5 maps which valve would give free as a SMALL part of an update. Bioware charges us for DLCs. Bethesda cut the support for fallout 3 already :/ despite many glitches remaining. Ubisoft are dicks for their freakin DRM...the most hated dev should be them.