I've said it before, but it really comes down to which emotion Lucas feels the strongest. His hatred for the earlier 'flawed' films or his desire to make money.

Once he gets to the point where a high quality remastered set of the trilogy on its original form is the last hope to make money, after he has saturated the market with release after release after release of his 'souped-up' special editions no longer makes money and the public is once again sick of all things star wars (remember 1985, anyone?) then I think he will have to relent and tap the last remaining fanbase who are holding out for bluray or what ever is acceptable at the time.