It would make sense that there would be no more changes to the current ST, or the look of the entire mk6 range for that matter, as it has been said a few times that the mk7 was destined for late 2007.

Like you just said it will be a whole new design once more. The only concept picture I've seen was this one ages back, which looks a bit like a small Focus (in the same way that the mk6 was the mk1 Focus's little brother):



I don't how long into the mk7 era it will be before another comes out, hopefully not nearly 3 years again though, maybe a year later like with the mk2 Focus at worst!

Possibly wishful thinking here but perhaps there was a little confusion in what the dealer has heard on the rumourmill and there will be a limited edition run sometime with the mk7, with a bigger engine, lowered etc. They could call it.... a Fiesta perhaps?