Once you get past the first screening call, I find you on social media, blogs, forums and read your posts, and see what questions you're asking on stackoverflow. Then we might move you to the next stage. All in all, you get a pre-screening from our recruiter (about 15 to 30 minutes), a screening call from a technical hiring manager (30 minutes), and then you talk three or four principal engineers (45 minutes each). This happens in days.
The only person that doesn't talk to you that is highly technical will be the recruiter. If you're hired and start work, we watch what you're doing, mentor as necessary. If you have the right attitude and are coachable, so long as you can string together coherent lines of code then everything else can be taught.