Unless you work for a video game company, odds are you'll never get a chance to play an unfinished version of a game. If you've ever longed to (and I don't know why you would), Crackdown is your chance. Crackdown is yet another sandbox game, but it sets itself apart with a unique premise (a superhero cop assigned to save the city) and then squanders that potential.
When you first start the game, you fall in love. The gameplay is tight and easy to learn, the graphics aren't mind-blowing but have a unique feel that works, and the sound fits the whole experience nicely. The longer you play however, the more you realize that the developers haven't added certain things. For example, there's really no story to speak of throughout, and the tacked on ending makes that fact stand out even more. Also, there's no real variety to the game; there is some illusion of choice, but really you just do the same thing over and over. Finally, the game is just missing character. Nothing feels real or interesting. Your character is just some silent brute, and the city itself is merely a collection of waling animations which add nothing; the streets might as well be empty.
Crackdown was a great concept and definitely worth a rental, one just hopes a sequal is on the way to capitalize on that concept in ways this game simply does not.