Thanks, WF - I saw that site, but I just wanted to be absolutely sure about what the position is right now! Thanks also for the other links you gave.
I rang NATS again today and managed to be put through to their medical centre (different to the CAA medical centre). I spoke to Dr Roberts who was very helpful.
He basically confirmed that at the moment the cut off in terms of short sightedness for an ATC initial medical is still -3 with no more than 2 dioptres of difference between the eyes and no more than 2 of astigmatism. He did mention that the JAA wide proposed regs will come in at some stage, but are not in force just quite yet.
However, he confirmed that given my age (29) my eyesight will be stable and thus at -3.25 (combined with my other eye measurements) I will have no problems obtaining an initial ATC medical. Phew!
Just need to pass the 'other' selection tests now...
p.