It's pretty remarkable how the practice of releasing smaller films On Demand simultaneously with, or even in advance of a theatrical release has spread (also currently available: Pontypool, Dead Snow and the fantastic Flame & Citron). But I'm not trying to shill for Comcast. I am trying to shill for World's Greatest Dad, which I ordered on Friday and enjoyed immensely.
The movie's, uh, interesting concept has already been discussed to death (we've been asked not to discuss it here for fear of spoiling the film). Some people think it's gross, which it is. But the movie is a unique combination of nastiness and earnestness, featuring the first great performance Robin Williams has given since -- oh, I don't know. One Hour Photo? It also stars a kid named Daryl Sabara, whom you may remember from Spy Kids, in what might be the year's most hilariously unpleasant role. If you don't recoil from the plot description, I implore you to check the movie out.
One significant drawback: it turned out that Comcast offered only a pan-and-scan option of World's Greatest Dad, damn them. So I am urging caution. I plan to see the film again in theaters anyway, but make sure you know what you're ordering. I believe Amazon On Demand has it in widescreen.