Wow, brilliant idea! I've been doing some speedread-training and realised how much I could improve my speed. Your plugin is ingenius I must say! What you really should do to it improve though, is remove the "-" at the end of a sentence where a word is too long so the whole word is displayed together (shouldn't be too hard to fix?). At the moment this can make it quite hard to read some articles. You should also make it pause when it encounters a heading.

Btw if you are looking for some help on devoloping it or promoting it, I might be able to help :)