Earlier this month we saw PS Home Online 1.86 Running on PS3 4.88 OFW courtesy of PS3 Scene developer @NagatoRevenge at DestinationHo.me, who let us know in PlayStation 3 News today on Twitter that Sony pushed live a PS3 Firmware / System Software 4.89 Update for their entertainment system initially released back in 2006. 
As always, it's NEVER a wise idea to update PlayStation Firmware in order to make use of such things as PS3 Custom Firmware (CFW), downgrading, homebrew, Webkit exploits, etc.
Download: PS3 Firmware 4.89 (EU) Update / PS3 Firmware 4.89 (US) Update / PS3 Firmware 4.89 (AU/NZ) Update / PS3 Firmware 4.89 (JP) Update
This comes following the previous PS3 OFW revisionalthough the official PlayStation Site hasn't been updated to reflect Sony's latest PlayStation 3 System Software 4.89 Update yet, however, to speculate it may renew the Advanced Access Content System (AACS) encryption key again to support newer Blu-ray movies.

Update: Below is the official PS3 System Software Update 4.89 changelog from Sony's Page:
Version 4.89
Signing in to PlayStation Network now requires a device password for enhanced account protection.
Account creation for PlayStation Network and some account management features are no longer available on the console. Use your PC or mobile browser to use account management features with improved performance, speed, and safety.
Cheers to @NagatoRevenge on Twitter for passing along this news with the image below.. if you haven't done so yet, subscribe to NagatosRevenge's YouTube Channel!
New PS3 4.89/PS Vita 3.74 System Software Update

Download: PS3 Firmware 4.89 (EU) Update / PS3 Firmware 4.89 (US) Update / PS3 Firmware 4.89 (AU/NZ) Update / PS3 Firmware 4.89 (JP) Update
This comes following the previous PS3 OFW revision



Version 4.89
Signing in to PlayStation Network now requires a device password for enhanced account protection.
Account creation for PlayStation Network and some account management features are no longer available on the console. Use your PC or mobile browser to use account management features with improved performance, speed, and safety.
Cheers to @NagatoRevenge on Twitter for passing along this news with the image below.. if you haven't done so yet, subscribe to NagatosRevenge's YouTube Channel!

New PS3 4.89/PS Vita 3.74 System Software Update
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