They changed some rares to blues, it seems. I noticed that the rare hand crossbow you could make turned from yellow to blue as well. Not sure what the reasoning was behind this, but I'm guessing it has to do with balancing out the items before launch. There's going to be plenty of things that are different from the beta when the game is live, I'm sure.
They're changing lots of things in the beta. Considering it's a different server than the one they'll be using for the released game in addition to the beta characters not being saved for release (not even for every patch), it's pretty much expected to see stuff like that.
Item turned from a yellow to a blue...