Just found this:

http://www.trdsparks.com/displayparts.php?Mdl_dtl=449&Part_cat=2&parts_id=387

Any comments? Looks appealing

Unless this just came out and the Borla web site is not yet updated, I'm willing to bet that this is an axle back. The only cat that Borla had for the xa / xb was a dual tip. There was some confusion when this exhaust first came out because Borla had incorrectly written a description of it as a cat back and it was copied as the description at nearly every e-retailer. Anyways, perhaps that is the confusion. Hopefully not, because a Borla cat back would rock. The only thing that makes me think this could be a new product is that the part # for the Borla rear section is 11741 and this has a part # listed as 12050. I wouldn't count on it until you talk to a sales rep or tech at Borla.

id just give borla a call to double check....and of course report back

I checked that link and everything indicates it's just the axle-back. The price is consistent with dealer pricing for the Borla axle-back, the picture shown on the page is of the axle-back, and the installation instructions you can link to from the page are for the axle-back.