Just an idea
From my own experience...
I was trying to get an invitation to Google Analytics for about 5 months. Logged on to the "request an invitation page" roughly every two weeks and submitted my email address... no luck.
I read a post within another forum that a member had recieved an invitation 3 days after he created a Google Adwords account.
For the cost of €10 I decided I'd give this option a go. 24 hours I recieved my invitation to Google Analytics and it kicks ass. I also have my €10 credit in my Adwords account which has allowed me to familiarise myself with the interface for future PPC campaigns.
It's just my experience (and another forum members also) and it might be a coincidence. However, it didn't cost me anything as I have €10 credit to Adwords, knowledge of the Adwords system, and an excellent Analysis package to view my websites stats on now.
Might be worth a try???