I started with the nachos -- no on the salsa, but yes on the cheese (of course) and jalapenos. They were actually better than most ballpark nachos, but I couldn't quite put my finger on the difference in the flavor of the cheese. It seemed to be a bit more buttery-tasting, maybe?
Next, I ordered the sliders (mini-burgers). They came with a slice of pickle and chopped onions already on the patty (ketchup and mustard were in accompanying packets), and were served with a side of Kettle Chips. It was pretty good.
I was getting full -- from the aforementioned food items, as well as the peanuts that we were snacking on -- but still managed to get a couple more orders in: popcorn that was billed as "fresh-popped and buttered" (yes, there was a buttery substance on the popcorn, but it definitely was not fresh-popped), and some sour candies (basically, Sour Patch Kids knock-offs). Neither was very satisfying, but I wasn't hungry anymore anyway.
Since it was chilly that night, I opted for hot chocolate the entire evening. It was water-based -- which was good and bad. Good because it meant the server could bring it out really quickly, but bad because... well, it's water-based hot chocolate. (The item that seemed to take the longest to make/serve was the mozzarella sticks. A friend of ours placed that order and it took about half an hour to arrive.)
Although I haven't been to an SF Giants' game yet this year, I think they still have the A's beat in terms of ballpark food.