Several models out there that will do nicely. Eureka! is sort of the gold standard in functional, well-made, well-priced family tents. Its Equinox 6 ($350) fits six, has a sturdy aluminum frame, and comes with a tough coated-nylon fly that sheds rain easily. Plus, its all seam-taped, so all you have to do is buy it and take it camping. At Internet sites such as Campmor, you can find good buys on other Eureka models such as the Tetragon 1210, which also sleeps six but has somewhat lower-grade materials compared with the Equinox (fiberglass poles, for instance). But at $200 the Tetragon is perfectly suitable.
One interesting recent addition to the family-tent world is Sierra Designs, which of course is better known for its backpacking and mountaineering tents. But they make a top-drawer, six-person tent called the Moken 6, which takes high-end backpacking tent design and materials and scales it up to this 54-square-foot behemo-tent. It actually can sleep more than six, as its designed to put three each in two side rooms, with a central common area for table tennis. Alas, the cost is $600, which is rather steep. Marmot takes the same approach with its slightly smaller (no table tennis area) Halo 6, for $450.
REI, meanwhile, can house you all quite nicely in its Hobitat 6 tent ($300). This is really quite a nice tent, with high-end materials such as aluminum poles and polyester rain fly, nice touches such as ten inside pockets, and room for a family. Plus its a good-looking tent, with a little style as well as lots of room. Itd probably be the one Id get.
The 2008 Summer Outside Buyers Guide is now on newsstands. Look for it online soon.