This is quite strategic. There are various reasons why we might prefer to take Wikitravel's route with the CC licenses rather than any variant of GFDL, IF we can get for instance the idea of "faction attribution" ("this has been accepted by the Green and Pink factions as being accurate, and since you trust these for your buying advice, we pass it on to you without comment") and the idea of "share-alike only for life-enhancing purposes" i.e. planet saving not planet killing, then, there's no reason the CSL can't be in CC form.
Also, travel advice is like buying advice, in fact, it's a form of buying advice. So there's every reason to believe Wikitravel might want to use the healthy signal infrastructure and help recommended services sell through a healthy buying infrastructure - which would pay for everything, wouldn't it?
We'll work on it. It's one more step AWAY from the mediawiki/GFDL mess, and the vile people who seem not to care about the way software violates licenses, sysops violate licenses and laws, etc. The further away, the better.