Have no idea why Audi have issues with the sun roof something about their supplier that can't keep there time commitments, you would think that Audi should be able to get a back up supplier on something like that if their primary has problems delivering. It sound like it come down to the point that they rather cancel the sunroof in the UK then have delivery problems with it. why just UK no idea
My Assumption (I'm in the US) is that US S5 will have sun roofs optional on 09 (std on 08 here)
I'm sure I had read somewhere that the fitting of the sunroof was causing production delays (hearsay). I have the sunroof in my S5 (UK - Jan 08). It is a bit boring, it only tilts and therefore you lose a bit of the fun associated with a sunroof with the tilt and slide type options.