If there is ever some kind of update to the Half-Life series (Which there'll never be really), then I'd be so ecstatic to see Garry redo the mod for the newer game... Although, it would take such a long time to get the game up to where it is now... They've really added a lot of content to Garry's Mod since it was originally released and it'll take a long time to move the codebase across from an older game to a newer one.... This is especially true when it comes to moddability, it's going to take a while for them to be able to build that into the new Half Life Garrys Mod as well.
"It never hurts to keep looking for sunshine" - A. A. Milne