Lisa Gannes and GigaOM has an interesting post on cFares. Love the idea but the worry with this site (and other niche like Groople) is whether or not a great niche product is enough to build a business on. To use a soft-drink analogy (which I am known to do) - how often can you base a whole business on a single product that caters to a particualr market - Red Bull - vs. when does your great energy drink better sit with a full service player who can pump "free" (in incremental terms) distribution, marketing and development - such as Coke launching "Recharge by Sprite". Don't know the answer but will see soon enough.
UPDATE - July 07 cFares have just closed a series A round of $4.5mm from Claremont Creek Ventures and Garage Technology Ventures (who were also an angel)