Sony may have hit some high notes last week with their E3 press conference, but this week they are getting kind of a bad wrap.
The latest firmware update, version 4.45 is known to be bricking systems, especially slim systems. Oddly enough, it seems to be ok if you are a Playstation Plus member. I downloaded the update last night without any problems, and have been playing just fine ever sense.
Sony is aware of the issue and currently working on a solution to it.