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Yes, such a branch could be established, but a) SVN branches are only useful if the development differs from the main development for at least some month and b) some dev has the possibility to check the code from time to time.
Right now I cannot see any needs for this branch, because the ogl extension stuff should be solvable somehow, and AFAIK no one of us has the PSP SDK installed yet. But we can make this branch very quickly once we feel it's needed.