Ah, so the only way to grab DoD source is to get one of the steam packages? That seems kind of lame of them.
I would think they would eventually offer DOD source, and maybe HL1 source, to people who buy the regular retail version of HL2.
Most likely through Steam, by paying additional $19.99-$29.99.
I also think they will eventually offer a third retail version, with all the software in the collector's edition, but not the t-shirt and strategy guide, etc.
But who wants to wait 6-12 months ??