Sony loves their firmware updates, which is why PSP users will have the opportunity to download the version 5.51, the latest update to the PSP hardware "soon," according to the PlayStation Blog.
The firmware isn't adding any new features, though. Sony's only promising some improvements to "system software stability during use of some features." Which features? Like other firmware updates, it'll be up to users to figure that out.
I can't wait to forget about this update, be forced to upgrade when I buy a new game and cry in a corner, as my PSP tells me I need to wait until it's fully charged to update. (That's mostly sarcasm.)