The mystery about the new firmware update is solved. The new Firmware 1.92 update is minor, and nothing else.

According to the senior PR manager Patrick Seybold, they released a minor firmware update that focuses on PS3 compatibility and playability issues for selected titles. A search site for looking up compatible titles will also get updated since it is in development.

There are no names for the the "selected titles", some rumors states it is "Warhawk" and "Liar". Search site update is definitely a good news since it has been very hard to find the titles on that list.

You can get more info on Playstation blog.