I will be going to the Whisky Fest this year in SF, and having been there last year, I can say that you'll enjoy this event.
The best thing is to browse the "Whisky Pour List" that will be on the web prior to the event. That way you can make a plan of attack for the begining of the evening. You will also be able to see what will be offered during the VIP hour, and then make a decision whether it is worth it to you or not. Here is a link that should have it in the future, and you can browse the list from 2008 to see what you might expect in variety.http://www.maltadvocate.com/docs/whiskyfest/san_francisco/whisky_list.aspx
My only tip would be to not try anything you've already tasted. Unless of course, it's a whisky you will probably not be able to taste in the future, such as some of the VIP offerings.
At my first event, I let the excitement get the best of me, and I drank far too much. Just spread out your sampling, and include lots of water, food and conversation in between. Last year's Whisky Fest was my second event, and I followed this practice and had a great evening.