Personally I was in between jobs recently, so I sent Google my resume using their online application site. After about a month, Google still didn't get back to me -- meanwhile I managed to interview at 6 different places (all the way) and found a new job.
"I heard nothing for a month and a half" is the key problem I think. It's going to be very hard for any full time employees that are any good to stay off the market that long, they'd have to apply to Google before quitting their last job.
As for interns, I am not overly surprised since you applied in December. At my school we had the hiring booms in October/November and then again in March/April (that's when we had the 2 engineering job fairs), so anytime between that people weren't really finding a new internship (unless it was on their own).
One last thing, what exactly is a Google spreadsheet beta candidate form? Is that the same one as the optional Google "survey" where you had to rank your skills (1-5 or 1-10 was it)?