Production of season 4 is in full swing -- cast and crew recently tweeted that they've started work on Block 2 (which usually means ep. 3 and 4 as each block consists of 2 episodes). There is still no word on further seasons, but
this article about Starz bodes well for Outlander being renewed beyond season 4:
And yet, Power isn’t the show that gets the most ink. That would be Outlander, which doesn’t get quite as many initial viewers per episode, but is probably the buzziest, most discussed and obsessed-over show on any cable network (aside from Game of Thrones, of course, and maybe The Walking Dead). Perhaps a more impressive number than the amount of viewers, though, is the fact that the average per episode is up over 40 percent from last season, and over 46 percent in the prime demo. Only two other shows on cable television had increases that high, and they were both HBO programs — Insecure and Ballers. While it’s true that Outlander is the only such show on Starz, it has served to legitimize the entire network.
And while we're talking about season 4, this is a video of some behind the scenes from a recent shoot (with cheesy music). What's most interesting about it for me at least comes at the 2:49 mark -- ROLLO!!!! Otherwise, it's mostly just (not that clear) shots of Jamie and Claire on horseback, riding through the woods, and stills of a rudimentary camp set-up and other props. But ROLLO!!!!