Thats a big negative good buddy. I found out the other day while researching this info(before joining this thread) that the subaru runs the same bolt pattern as VW. Which would be 5x100. Tis a shame really that the xB's don't run that pattern cause I have some killer wheels on my Jetta that I would love to put on a xB. 18x8 front and 18x9 rear. Five spoke, black with polished lip. The lip on the rears is wide enough to accomidate my cell phone.
However I do believe that the scion xB's will accomidate any wheel that can be run on a Jeep, bolt wise not sure about offset.
The Jeeps run 5x4.5 which if I did my research right is the same as 5x114. Which I hope is right because I have a set of rims I bought for my Jeep that would look killer on the xB if they fit right.