Another way to say that something is really swell; or your really satisfied with the outcome of a particular incident. A "catchy" kind of phrase for some "old ass" white person when they think something went down really nicely.Goofy caucasion remark when they're exuberent about something.
Yo Pete! That's a real swing'n deal you got on those golf clubs!
Oh Martha! That's such a swing'n outfit! I think Johnny will really like it!
Construction Joe : Hey Teddy, I think I can finish your kitchen countertop and tile floor by tommorow, around 3pm.
Teddy : That's swing'n!