Looks like Sony was quick to move on the release of a new firmware update. version 2.01 is available today if you use Network Update on a Japanese PSP. This is a small update that apparently only repairs the image based exploit. If you ever want the ability to run homebrew, I would hold off on this update.
If you *really* want to run the latest and greatest firmware, and you have a Japanese PSP, run network update to get this release.