We spent some quality couch time with the program over the last couple of days, and with a powerful PC, fast internet and WiFi connection, we found video quite watchable on our iPhone 4, and there's no knocking PlayOn's breadth of content available, with loads of TV, a good deal of anime and your entire Netflix streaming queue available on the phone. The interface is barely there, though, just a series of poorly-spaced nesting menus, and it can take quite a few touchscreen presses and a bit of thought to find what you want to watch. There are a few bugs too, like one that kept shooting us back to the main menu randomly upon a button press, and another that locked us into a particular piece of content until both app and desktop server were restarted. Some content could have looked better on the 3.5-inch Retina Display if only we'd had the option to press the HD button, but the only controls Media Mall provides are forward, backward and volume, and even with full bars we're afraid we couldn't get 3G playback to work reliably. Since the company still offers a free 14-day trial of the service, the software's definitely worth a try, but if you want Hulu or Netflix on the go (or even around the house), we imagine you'll eventually end up using their dedicated apps instead.
Update: PlayOn's PR team tells us some of the exact bugs we found have already been fixed for tomorrow's launch, including crashes that return the user to the main menu, and system states that chain the user to a previously selected video. That's an impressive turnaround!
Update 2: The same team just pinged us again, and it looks like they've hit a roadblock. Apparently the app is once more "in review" under Apple's watch, so only Cupertino knows when exactly it'll be released to the world. We'll let you know as soon as we hear more.
PlayOn for iPhone hands-on