iPad of course, has a couple years' head start on the whole industry, so they've sort of set the standard. But for those who don't want to spend $500 on a tablet computer, consider the recently-launched Galaxy Tab 7 Plus and the Nook Tablet. After all, it isn't fair to compare them to the iPad because they are not 10-inches and they don't have 3G.
They are both seven-inch tablets that work with a Wi-Fi connection and can deliver excellent quality content from separate universes. The Nook Tablet is a hybrid e-reader/tablet that is really a vehicle to Barnes & Nobles' extensive library of books and magazines. With its $250 price tag, it's hard to discount the Nook because it has a snappy LCD display that at least matches the Galaxy Tab's WVGA display.
Furthermore, while it's true that both run the Google Android system, the Nook Tablet version does not allow it to use apps from the Android Market. Maybe that's not important to some people, but there are thousands and thousands of apps out there that Nook users will miss out on.
Besides the screen and the price, the other big difference is the lack of a camera on the Nook. Galaxy Tab has a front- and a rear-facing camera. However, that too is a trade-off because, while not a huge drain on the battery, a device without one will have more power to run the other functions. In tablet warfare, there is but only one winner, and it is the Nook. Cameras on tablets, while fun, are not super wieldy, and in this case, not worth the extra $150 for the Galaxy Tab.
Tell us in the comments if you have a tablet computer or if you are still waiting for the inevitable laptop/tablet convergence.