Ugh, I don't like the recently revamped UI on the PS3. The design is opressively dark, with the black ground making the text difficult to read, and the shading done on the dvd cover tiles and thumbnails.
I have a Roku box, and I like that interface. It's easy to read, quick to browse. Of course, the interface I'm using is for a Rokue N1000, which is the 1st Gen Roku boxes, and their update stops at 3.1, while I believe the new interface for Roku 3s and higher is 5.0, so one's mileage may vary depending on what one has.