I would suggest doing a blog search regarding Google interviewing techniques, there is a lot of information out there (a lot of it negative, just so you know) but you can also gleam some helpful hints into the process that Google uses for recruiting and interviewing.

I applied for a position in Ann Arbor, MI, however the process in Mountain View may be different.

Google gives the impression that they are not so much interested in a persons qualifications, but rather the person and how they would fit the Google culture, this is not the case. If you pass the telephone interview (FYI: a lot of the recruiters that work for Google are contractors not Google full time employees) which will include some technical questions , they will ask for your transcripts before you can move onto the next stage which is an online evaluation relative to the position you have applied for. Once you have completed the online worksheet, your file and results will be reviewed by a selection comittee. This is as far as I got in the Google process. I assume if you move on from this point, you may actually get to meet face to face with some of the people you would be working for/with, which from what I have been told, an onsite interview would take up an entire day.

I would suggest that if you be yourself and be confident about your abilities, you should do fine.

I hope this is helpful, and I wish you luck in your interview.

Definitely you have to be strong in your technicals, you must be familiar in the product group you potentially will be in charge of, and show them in the interview that you are enthusiastic to learn new things as well. It is very competitive to work for Google, and the interview process is long and detailed. I suggest that you read their job description and responsibilities in the job posting carefully and try to answer all the questions that are in line with what is expected of the job. It always works for me.