The space inside is open and inviting, and the decor is very classy - lots of wood and brick. There are shelves with old issues of National Geographic along with an old piano in the back. There's also a great outdoor garden space with a fire pit that will apparently be used for grilling in the warmer months.
Their beer selection is pretty good (Blue Moon on tap suits me just fine), and the bartender Ryan promised that they'd be rotating a few of the beers on tap from time to time. One interesting tidbit is that they don't have any Brooklyn Brewery beer, which is fine with me since while it's all right, you can get it at every grocery store and crappy bodega anywhere in Brooklyn. They've also got a decent wine selection for a bar.
We got a chance to talk at length with the owner, Frantz, whose goal with Rustik was to bring an old-fashioned tavern to the neighborhood. Their website boasts that Rustik is the best bar in Clinton Hill, and even if I didn't live literally around the corner I'd be inclined to agree. If you're anywhere nearby, do yourself a favor and stop in. My first impression of Rustik is that it's a really special place, and our neighborhood is much better for having it.