I would say it's not worth the trip unless you've got a plan, and already know a few people in the Valley who you can meetup with, and who can introduce you to the local scene. SV isn't particularly worth seeing as a tourist (it is basically a cultural wasteland, although Stanford is a nice campus and of course SF is a great city). The great work that is done inside the buildings isn't really apparent from the outside.

So if you decide to come, definitely plan ahead.