Firmware 3.15 now mandatory
Maybe it’s because it really only brought Minis compatibility and the data transfer feature to the table, or maybe it’s due to the rumour that 3.10 was proving to be problematic with certain games and may be the source of a recent spate of PS3s dying.
Either way, you can’t escape 3.15 anymore as it’s now mandatory. Unless you want to stay off the PSN that is. And who’d want to do that? As a wise man once said: what is this? 1995?