I like web OS.
Being a BB user, I think web OS is the easiest adjustment due to the cards. That's a great idea.
Only downside to web OS is its not as customizeable as the BB (when it comes to options/settings), is not as popular as say android and after all this time, really only two device choices! Palm needs to expand on their lineup.
Using and moving about on the phone is great, it's something to have to learn first then its easy (luckily there's a walkthrough when you first power it on) but navigating can be tiresome and take a little bit more time than needed.
Unlike the BB which is quick, simple and everything is in reach. Its like being in a Lotus Elise vs a 7series BMW