I really like this promessing plugin project for multi language support. Currently testing on multi-site, it does not have the drawback that qTranslate has: increased loss of speed when browsing.
But there are still a few downsides (which is completely understandable for such a new project) ... I'd like to bring up one for discussion if I may (or has it already been discussed?)
I had set up a static home page, and next activated/configured Polylang, the plugin allowed me to add translation pages of the home page just fine but... Let's say I set up a page called Home as homepage and then created a translation called Accueil (French) for it, then when visiting the front end home page for the French language that home page does not have the body class "home" anymore... In the case of my site, this breaks specific front page CSS rules :(