Samsung Galaxy S 2 ICS Problem

This is mostly one for UK posters (i think)

I'm reading on a few websites that O2 have released ICS for the Samsung G S 2. I have a Samsung GS2 on O2 and yet whenever I plug it into my computer (Mac if it makes any difference?) Kies tells me that my phone 'isn't able to upgrade software via Kies'. This happened a few times.

Now when I connect it into my computer it tries to connect for a few seconds before saying the 'device is not responding'.

I've upgraded to the latest version of Kies through the Play Store and the latest version on my Mac. I've also tried going through the Settings and selecting 'Software Upgrade' ('There is no software upgrade').

Am I just doing something stupidly wrong? Is ICS even out for the GS2 on O2? If it is, why does Samsung make it so freaking difficult to upgrade my phone?