There's been no confirmation from Sony themselves but an interesting scrap of information has made its way onto the Internet, fancy that. Apparently the PlayStation Store could very well be having a day or two at the coder’s saloon and spa for a complete design makeover.
From Kotaku and their sources, the graphical user interface will get a major overhaul to coincide with the US release of Gran Turismo 5 Prologue, which hits April 15.
Navigation would apparently change into a series of buttons along the bottom of the screen, resembling something close to the SingStore which is available through the PS3 release of SingStar. Of course this is only rumour and I'm sure no-one would be malicious enough to spread false rumours, on the Internet of all places.
Edit: Click here for the Kotaku article.