After looking through meetup.com and seeing a few meetups planned uncertainty and indecision set in. Naturally, my first reflex is to ask a question on YC.
I'd also recommend looking at webwallflower, which lists a lot of networking meetups not on meetup.com: http://webwallflower.com
There is a NewTech meeting the first Tuesday of every month at DLA pipers in Palo Alto. They have 3-4 demos of products(typically web apps) followed by networking. It includes free pizza/wine/beer.
This is a great meetup, the only problem (for those of us that live/work in the city) is the PA location. Although sometimes they do meet at the DLA Piper office in SF as well.