As for standing in the rear of Green Card line, itdepends on how you read it. If we read as you are reading it, where they are is irrelevant since that line is longer than 6 years and the guest worker will have the ability to come and go so that he will be able to apply at home. If anything, it benefits those who come from futher away(Asia) over those whose home is close(Mex).
What Bush has proposed here is not binding and is entirely up to how Congress wants to work out the details.
That line can be read either way. An annual increase would be a yearly increase while an increase in the annual limit could mean a one time increase. Likely deliberately vague. The greencard language benefits the mexicans more by simple numbers. They have a 20+million head start.