Actually the Tucson has more interior passenger space( more front and rear leg room and head room--more shoulder room) and more payload capacity than the X3--just less cargo space and is $20k less starting price.
Lets wait to see the specs on the VW--Im' sure the price will be less than the X3 and will have the VW solid build and be a great driver. I like my X3 but it is just a little pricey --the VW dealers will give better discounts (judging from past experence of 2 Passats I owned)--than BMW.