Yep, takes both. The arm is slotted for pinned blades, and has two adapters you can clamp on the end, then hook over the arms. There's an Allen wrench you use to loosen/tighten the adapters (I cannibalized a fridge magnet for the magnet itself, and use that to help keep track of the wrench).
One little quirk, the tensioning issue returned today, cutting into 1/2" whiteboard from Lowes, probably only a step-n-a-half above cutting into balsa wood. So I knew it wasn't that the board I was using previously was too thick. I did a lot of Googling, found nothing (Wen's site is horrible....you can find all sorts of "hey, our products rock! Here's a rah-rah page we wrote about it!", but NO Support links or FAQ's or forums. Their 800 number is Mon-Fri 8-5 only, which sucks cuz I have a full-time job that DOESN"T involve a scroll saw or any other Wen products. I did a bit more tinkering, and discovered that the post the locking lever sits on....appears to be threaded somewhere in the bowels of the saw. Some quick righty-tighty-lefty-loosey, a bit of fine-tuning to keep from popping the blades off from over-tension, and I'm back to cutting again.
Its not a bad saw, it has a lot of nice features that my old Dremel didn't have (like....everything), it cuts well....just keep an eye on that post.
Here's the stained/varnished product: