I have previously attended the University workshop with the folks in Sydney (you may know Mindy Thomas, previously from Atlanta). It was actually styled somewhat differently and I feel the UK event missed out on the chance to speak with pottential and existing clients more directly, through the 1-on-1 'maximisation' sessions used in Sydney. Google also neglected to have a stand on the exhibition floow. There must be many smaller firms who are not hunted down by Googles sales team, yet are really eager to understand more about what they here so much about in the press.
Aside from that, it was also great to have the opportunity to speak to a few Google staff. As you know AWA, I am still on the hunt for an internship with Google and it was very interested to quiz some of the team on the recruitment process and the type of stuff they are working on here in the UK. Didn't get much intel on the secret Oxford project though - "no comment" to all the VoIP rumours... and also no vouchers! :(
(Please let me know if you have any specific questions AWA / Others)