As of now in most regions the new official Vita firmware update 2.5 is live and is mandatory.
After reporting on the firmware update yesterday and then them pulling down the information from the update page they’ve decided to blind side us with the 2.05 vita update today. But after the UNO exploit release we knew it was bound to happen at some point or another. The update was quite lengthy to download and to install so as to what Sony decided to do with the update other than blocking the UNO exploit is unknown until further investigation. Oddly, the update also required for a system reboot which hasn’t been the case before. Undoubtedly it did patch the usermode and kernel exploit for UNO. The update is already live in the US and should make its rounds to everyone else at anytime.
The change-log included doesn’t offer any other details other than the standard “System software stability during use of some features has been improved.” However it patches the UNO exploit for 2.02 and below using the typical black list method making the exploit unable to load and shown as corrupt. If you’d like to keep your UNO exploit or any previous exploit released do NOT update to 2.05 or you’ll no longer have access. (Remember that all tricks and proxies have been blocked so you’ll be stuck without direct PSN access on your Vita.)
If you have decided to stay on a lower firmware you’ll need to make sure you have Open CMA installed so you are not blocked from copying content. By some chance if you missed the last few exploits, go ahead and update and wait the next release. Also keep in mind when deciding to update from a previous exploit that there may be a chance that the next exploit release is not a kernel exploit but rather usermode (VHBL). The main difference is that kernel exploits allow for full access to the pspemu giving us eCFW (TN-C & ARK) which lets you run PSP/PSX backups, homebrew, plugins ect. compared to VHBL which is limited and only allows homebrew.