Got a phone interview for the Kindle team through friend working at Amazon. Not much was known from the job description which was pretty generic and practically useless.
The recruiter setup a phone interview in which they asked one coding question and a design question.
For the coding question I was asked to write code in a collabedit window.
The design question was one of the questions which some blog (apparently by an Amazon employee, strangely enough) recommends NOT to use in a phone interview. Apparently this guy missed the memo.
In general, the process was unorganized: I was contacted by two recruiters!, who sorted it out later and only one was chosen to be representative later. The interviewer was quite stoic, monotonous and seemed to have been forced to take the interview (of course, that is just my perception). Amazon is hiring like crazy and recruiting folks must be swamped, so it is understandable.
Advice to other candidates: Do prepare for design questions.
Ask a lot of questions, try to clarify as much as possible. The design questions they ask are open ended and some of them who are clueless ask the ones which are unsuitable for a phone interview (too involved, according to the blogger from Amazon). So it is even more crucial to narrow down the problem as much as possible. Especially so if you are interviewing for a Senior position.
They are OOP fanatics! So, don't mention generic programming or Alexander Stepanov. (Just kidding, ignore this sentence).
In general, interviews(especially phone) are a hit and miss (not just for Amazon) so try to stay relaxed (I know how hard it can be!), don't rush (i.e. think carefully) and try do your best.
For phone interviews, if it is hard for you to stay relaxed, it might be a good idea to write down "RELAX" (and other such advice like do your best) in a file and keep it open, so you can look at it periodically.
Ensure you have a steady internet (for collabedit type stuff) and phone connection, keep a bottle of water and some paper+pen (or whiteboard) handy.
And yes, don't forget to let the interviewer know your approach/thinking, as it would let them guide you onto the right path if you are going down the wrong one, and it lets them know your thinking process, which is what they (ideally) should be judging.
Good luck!