I forgot they were doing this so I have yet to actually try it out. Has anyone here made use of it yet? I believe it is still in beta and they are working out the issues and optimizing it for user experiences right now.
Here is a bit on it from PC Gamer:
If you’re not familiar, Remote Play Together is a feature on Steam that lets you bring others into local multiplayer and hotseat games even if they’re not physically present. It’s a godsend for lots of games, especially those hardcore local multiplayer games that are hard to get four people in once place for, or for hotseat on wargames, where multiplayer service is rudimentary or limited.
We’re of the opinion that Remote Play Together is one of Steam’s best features. The ability to turn a local multiplayer game into an online multiplayer game is powerful—and now you can do it with friends and/or grandparents whose 15 year old potato PC can barely run Steam.