Call me a cynic, but maybe they'd let you in if you paid up a big sponsership fee... :(
I guess that' the problem of being a .NET developer trying to join a non-MS focused event.
Roy,
Maybe you place too much emphasis on the limelight. Developer fame is hard-earned and tends to be short lived, things change fast and the past is quickly forgotten. There are masses of extremely talented designers above and beyond the conference presenter, they have no interest in the popularity contest.
Rest well on the fact that you are an innovative developer with skills that will endure the test of time, you will feel less pressure and you wont lose any significant opportunity.
If the reviewers know you and have seen you before, and know you, you are more likely to be accepted.
I read > 100 submissions for a different stage. Too many people thought a few paragraphs were enough. But the best submissions (especially for longer sessions) provide a whole lot of detail about the topic and the speaker, if they don't know you.