E3 2009: Sony promises 'extensive line-up' of UMD games for PSP Go! launch
Older UMD games to be re-released digitally

The PSP Go! hasn't exactly blown our socks off yet, as its essentially reduced functionality is coming at quite a high launch price. In an effort to bolster support for the new PSP hardware, CSE Worldwide Studios president Shuhei Yoshida told Develop that an 'extensive' line-up of games will be ready for the system's launch.
"We have been working to release our UMD titles, old and new, via electronic distribution so consumers who buy PSP Go will have an extensive line-up of games to choose from on day one," he explains.
There was no mention of what sort of price we can expect for a digitally distributed PSP game, or indeed which UMD games are to be re-released.
Given that a UMD offers up to 1.8GB of data, there's some concern that the PSP Go!'s 16GB of storage could run out quite quickly. Currently, however, the PlayStation Network allows re-downloading of previously purchased titles free of charge, so it's possible that an online games library could be maintained and downloaded when required.
"We are also working on some titles that take best advantage of the form factor of PSP Go, like games that you can play with the screen closed by using only the L and R buttons for example,” continues Yoshida, who went on to point out that previous models of the PSP will still be compatible with this new digital distribution system.