Update: Firmware is out. Check Network Update or grab it by clicking here.

Sony just announced that firmware 5.50 for PSP is due out tomorrow — April 21. The update will allow users to browse the built-in PSP store without a registered PSN account. Of course, you’ll still need to register an account to purchase anything.

PSN integration will also be enhanced with the arrival of version 5.50, as a live news-ticker detailing the latest offers from the store will be visible from the XMB. Additionally, another key, and perhaps overdue improvement is the ability to create subfolders for media such as photos, music, and videos.

Specific to North American PSP owners is the inclusion of Trend Micro security software. You’ll be able to access a free trial of the software by installing this firmware update. When enabled, it provides parental controls and technology that automatically scans for inappropriate content.

More details are after the jump.

London – April 20, 2009: The doors to PlayStation®Store have just opened wide thanks to the latest system software update for PSP™ (PlayStation®Portable). The v5.50 upgrade means you no longer need a PlayStation®Network account to do a quick bit of window shopping – you can check out all the latest games, trailers and demos available for download from your PSP.

But that’s not all the upgrade offers. PSP users will now be able to view PlayStation Network’s Information Board on the PSP system’s XMB (XrossMediaBar) interface– the live news feed detailing the latest exciting PlayStation Store offers – on their screen (as long as they are WiFi connected).

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