Here are a few updates from Total_Noob and teck4 (teck4.com/blog/?p=453) and also hiroi01 (hiroi01.com), as follows:
CEF 6.60 TN-A MHP2ndG
Custom Emulator Firmware 6.60 TN-A. For PSVita 1.80 with MHP2ndG (Monster Hunter Portable 2nd G) Exploit.
eCFW 6.60TN-A H.BIN mod
Modified H.BIN for VHBL on PSVita 1.81 with Urbanix Exploit.
Code:
[eCFW_6.60TN-A_H.BIN_mod.zip]
This works on any usermode exploit(probably)
Thanks to Total_Noob, Coldbird
Special thanks teck4
CEF 6.60 TN-A MHP3rd
Custom Emulator Firmware 6.60 TN-A. For PSVita 1.80 with MHP3rd (Monster Hunter Portable 3rd) Exploit.
From wololo (via wololo.net/2012/10/08/release-6-60-tn-a-h-bin-mod-by-hiroi01-run-tn-hen-on-any-usermode-exploit/):
6.60 TN-A H.BIN mod by Hiroi01: run TN HEN on any usermode exploit
Good news, everyone! If you happen to be running VHBL on one of the previous exploits such as Monster Hunter, this is for you: Japanese developer Hiroi01 created a new loader that makes Total_Noob’s 6.60 CFE TN-A compatible with your game. That’s right, this is not limited to Urbanix anymore.
Please note that I haven’t tested this yet, and I suspect it might only work on 1.80 and 1.81, so technically this could be a solution limited to Monster Hunter owners (as far as I know, some offsets are different between all these firmwares, and that could prevent TN’s exploit from working correctly on earlier firmwares), but please give it a try and report success or failure.
Installation is relatively simple, but requires you to follow the steps carefully, don’t mix up the files 
- Get VHBL for your user exploit (for example, VHBL for Monster hunter if you have Monster Hunter and are running on 1.80). The purpose of this step is not to get VHBL, but to get the exploited savegame for your game. VHBL is actually not used at all in this process.
- Get Total_Noob′s TN-A for Urbanix (yes, it’s the Urbanix version, at this point it does *not* matter that you don’t have the game Urbanix
- Get Hiroi01′s mod (attached below)
- Replace your VHBL’s H.BIN with the H.BIN from the mod
- Install all of that to your Vita with Open CMA, and run the exploit like you would normally run VHBL
- TN’s exploit should load.
Again, I haven’t tested this yet, so please report failure or success 
Finally, from HGunified on YouTube comes what allegedly may be the next exploitable game (Mad Blocker Alpha: ROTF) from PSN... although unconfirmed by PS Vita developers at the moment along with Angry Birds - Mini Game also. Below is the video:
Missed the Urbanix exploit? TN will soon release a port of his CFW to the PSP Mini Mad Blocker Alpha : ROTF. I am doing this Ninja release in a hurry so that you can grab it asap if you are interested. The port is done and beta tested, although I haven't tested personally myself. For those of you with Monster hunter or Super Collapse3, at this point I would say the decision to update and buy this game is entirely yours.
TN announced the release for Tuesday, so if you're interested you should buy the game before that. It seems the game is available in US and EU stores, but not on Asian stores (JP, HK,...). If the game is not available in your region, the best solution is probably to create a US or EU account.