I'd like to have reservation systems available in the Site Application Packages. I've lost a few potential clients from restaurants, hotels and bed & breakfast owners because outsourced reservation packages have been too expensive, too difficult to implement, have too few features, had to be hosted externally or could not be private-labled.
I doubt if there is one application suitable for restaurants and hotel/B&B clients but separate applications would be okay. I have also found that most hotel reservation applications are too complicated for B & B's which, usually only have a couple of rooms and are run by "mom and pop" operations.