Everything was going well - I was out the door at 9, which should have been just enough time. I took a few wrong turns but still manager to arrive at around 9:31, figured out how to buy a ticket, and then saw there were two tracks. I saw a sign that seemed to imply the first set was for express trains, so I crossed to the other side behind some other people and looked around a little. Just then a train started to arrive, and the little pedestrian gates closed so I couldn't get back to the other side, and lo and behold I was on the wrong side. (later confirmed by an actual sign) So I had to wait an hour for the next one. And just a few minutes later the limo from my hotel pulled up and (presumably) dropped someone off. That would have saved a lot of walking.
Caught the next Caltrain (which was very loud and big) to San Jose, and then had to wait for the light rain to downtown, which wasn't too far but I wasn't sure I could walk under the freeway. The Caltrain runs every hour on weekends and the light rain runs every half hour, so I had a lot less time than I planned in the city.
Which turned out OK because I was tired of walking around. I checked out the Tech Museum of Innovation (pretty neat museum, especially for kids) and had a nice lunch at a local cafe, with tea even! It was still an hour until I had to catch the light rain but I convinced myself to at least walk along an island to the art museum, which was nice. It was still early but I didn't want to tire myself out before having to walk back to the hotel, so I went to the light rail station and promptly got on the wrong train. Easy enough to get off and take one the other direction, but I just missed the real train so I had to burn another half an hour sitting and reading. Arrived back at the hotel uneventfully but thirstily (was a little chilly in the morning with no sweatshirt, was a little warm in the afternoon) - and what kind of hotel doesn't have a water fountain in the lobby? The desk clerk helpfully informed me that there were water bottles in the minibars.
Thus ends the trip wrapup; pictures are all up now: