Update: Sony has pulled PS3 firmware update 4.45 after it was found to be causing errors in what the platform holder termed a "small number" of consoles. In a statement, Sony said that it’ll inform users once the problems have been rectified and the update is made available again.
Don't update your PlayStation 3 to 4.45! Dozens of users on PlayStation's official U.S. forums are reporting that the latest patch, which went live earlier today, is leaving their consoles stuck without an XMB interface.
The firmware update is intended to improve system stability and add options for in-game trophy notifications. It may well do that, but the folks who are stuck looking at the system's sparkly wave pattern without anything to interact with aren't deriving much benefit.
Restarting the system and other recovery attempts do not appear to resolve the issue. If you haven't downloaded the update yet, avoid it until Sony gives the all-clear. If you have downloaded it and can't access the XMB, sit tight until we know more.
We've reached out to Sony for comment on the issue and will update with any response.