It's really not. The problem with both Android and webOS is that lock you into their respective userspaces since both Palm and Google decided to put together their own basically from scratch. Nokia went the other direction and modified desktop libraries for use on a mobile device which is why it's reasonably straightforward to run regular Linux applications in Maemo and vice versa. The same is not true of either Android or webOS. For Android you need Davlik, for webOS you'd need a lot of hacking.