The buzz is starting to build about the P900, Sony Ericsson’s successor to its well-regarded P800 PDA phone. Some early reviews are starting to trickle out, and The Register is reporting that Sony Ericsson will officially announce the new phone on October. Mobile Review got to play with one of the phones, and says that it has a nicer stylus, a better digital camera, a higher-resolution screen, and a sleeker design than the P800, but otherwise the P900 isn’t that radically different than its predecessor. (They also tease us by mentioning that a cheaper version of the P900 aimed at the youth market is expected sooner or later, and that a year from now Sony Ericsson will introduce a second-generation of phones with support for WiFi.) Between the P900, the Treo 600, and all those new Smartphones, October is shaping up to be a very good month for PDA phones.