Well, UMDGEN v4 has been released.  UMDGEN is a great program for ripping and adding stuff into iso images, and also for saving isos in different formats.  Today, v4 has been realeased, and here's the changelog:

v4.00 changes:

* New layout
* UMDGen now displays information from UPDATEPARAM.SFO as well as PSP_GAMEPARAM.SFO
* Optimize button added. This function automatically detects and resizes dummy data, removed un-needed padding and dummies the contents of the UPDATE folder (if detected)
* Non-PSP standard images can be forced to be read by the user. Upon detection, UMDGen will let you know the image is non-standard and you can choose whether to continue and have UMDGen attempt to read it - *NOTE* depending on the individual image, this could cause UMDGen to close if it encounters data it isn?t expecting - but the general rule is if the PSP can read it then presume UMDGen can too.
* UMD_DATA.BIN file generator. If your compilation is missing this file then UMDGen gives you the oppertunity to create a new one.
* Ability to change ?PSP_SYSTEM_VER? in PARAM.SFO to different firmware version. (Use +/- key while version is selected)
* ?Drop Open? images re-introduced due to a lot of requests to re-add it to UMDGen.
* Complete CSO + DAX support. You can now edit compressed images the same as uncompressed images. Dax support now includes the use of Non-Compressed areas feature.
* ?Ezip? format removed. We didn?t think it was worth keeping this format since it only had very limited support anyway.
* ?Dummy File? option added as requested by many users.
* v3.50 still had trouble with one or two problem images. A lot of code to do with the reading/writing process has been restructured and these problems should now be fixed.

Want a quick and easy way to run UMDs, ISOs, or Demos that require 2.8x on your SE-B'' PSP? Here it is!

WARNING: This method flashes files to your PSP. By flashing these files, you agree to all risk to your PSP. While Dark_Alex's recovery menu should fix bricks, it is not guaranteed. COnsider yourself warned.

This method is similar to the 2.71/2.80 hybrid Devhook mode, except no Devhooking is necessary. If you want to stick with 1.50, use that method. For those who aren't fmailiar, this will flash several 2.80 PRXs to your memory stick, and tell your PSP to load them upon launch of a 2.71 kernel game.

The Advantages :

1) No need for devhook, this is direct from the XMB!
2) Works with no umd in drive!

The Disadvantages:
1.) It's impossible to load a game with plain modules disabled (due to the utility.prx). this unfortunately means that any game that needs to have the plain modules option disabled (SOCOM 2 for example) will not load. The only way to load them is through the Devhook method.

The rest of the installation instructions after the jump!