I have this book as well, and found it to be a worthwhile read. I got a few ideas for my own user group from it. I think you'll like it.

One tactic I've found to be very successful is reducing the amount of time people have to speak.

Instead of having one guy talk for an hour (very intimidating to new speakers) pick a theme for the month and have 4 or 5 guys talk for 10-15 minutes on the topic.

Definitely worth a try. Most people can talk about a topic of interest for 10-15 minutes without even trying.

Also, consider offering a roundtable discussion format for one of your meetings... skipping the speaker altogether. Get people discussing a specific topic, and occasionally jumping up to draw something out on the whiteboard while the discussion continues.

Awesome! Glad that I was able to help out by providing that review! :) Oh and Chris did an awesome post just recently too on how to help a group out as well.