It's updated constantly, that's the point. It's designed to be a mod engine to incorporate tech as and when it comes (when everything started using HDR for example).Mantonio said:The Source Engine is still a competitive gaming engine (hence why it's still in use). Of course they'll update it when necessary, but it's aged well and, well doesn't really look like it NEEDS an update right now.
HL2 can still keep up with a lot of games today, Episode 2 was very good looking and since when have L4D + sequel looked outdated?! TF2 is very pretty as well.
I think people forget that HL2 came out 5 YEARS ago. They can adapt it to anything.