Hold the phone... I didn't know that. Where can i get more info on this? Just curious.
There isn't much information on it beyond that really. Along with fixing some entry points and exploits, 3.61 also changed the encryption keys used to decrypt eboots on the system. This effectively blocks us from playing 3.61+ content, as we can no longer bypass the encryption (which is essentially what's done for pirated games, we don't actually own the private keys for the Vita, we're just bypassing it/using hacks to get around it).
To play 3.61+ content, we would need one of the following:
The 3.61 private keys
A new exploit for 3.61+ that gives us kernel access
The first is all but impossible. The only reason we got these in the PS3/PSP days is because Sony fucked up their security pretty badly. This is not the case with the Vita, where security was done properly (which is why it took so long to get something as fully fledged as Henkaku).
The second would render 3.60 obsolete, as we'd have kernel access on 3.61+ and would essentially be able to use Henkaku or a similar level of hacks.