Just a heads up that the 2009 SCMWA Pinot Paradise event is coming up at the end of March. This is a great chance to try a huge range of wines from all over the mountains; pretty much every Pinot producer in the area attends the event.
The main tasting event is in downtown Campbell on Sunday March 29th at Villa Ragusa, and I highly recommend it. There are around 30 wineries participating and the venue tends to be a lot less crowded than events like ZAP or Pinot Days, which means there's enough time to visit most if not all of the tables. Tickets are $55 in advance, $65 on the door.
On Saturday 28th there's the "Pathway to Pinot Paradise". You can visit 22 wineries, some of which don't normally open except on passport days. Some may be pouring older vintages or barrel samples; it may be worth calling ahead to see what's going to be on offer. At $25 the price isn't bad, but the distances involved make it hard to reach more than 4 or 5 wineries. Your best bet is to concentrate on a particular area; decide your itinerary in advance and print off maps or have a GPS. If you haven't visited a winery before it's worth checking with them in case they have any driving tips; some roads in the mountains look more like World Rally special stages.