An innovative demonstration of the Wiimote's capabilities... but little more.
Wii Play comes packaged with a wide range of simple "mini-games" if games is even the right term for half of them and the most entertaining will always end up being either shooting or billiards. Other than that there is a decent Mini-Tanks game, an equally motivated but not so entertaining cow racing game, a pingpong-esque pingpong (in which players simply slide their paddle left and right to return the ball and do not actually control striking the ball as in Wii Tennis, a futuristic lazer-airhockey, and then half a dozen Mii-motivated demos such as rotating your character to fit into a pose in a bubble, or picking some from a crowd of other miis.
The problem Wii Play suffers from as a game is the same as Wii Sports, only to an even more severe degree. The "games" are not all that entertaining after more than ten minutes of play. While I was able to manage a few rounds of pool and the shooting range, others quickly lost flavour and entertainment, what little there was to begin with for some such as the bubble game (but fear my 700 points anyway).
As a tech piece intended to portray the wiimote's capabilities as well as develop the user's understanding of the control system Wii Play is about par with other development tools; however, you'd be just as good off simply picking up an actual game. The only reason to get Wii Play honestly is to pick up that $40 second Wiimote for your system and the $10 demo set that comes with it.