Stephen Foley: Analysts at odds over Amazon's growth

US Outlook: Forget the rivalry between Apple and Amazon (the iPad will have outsold the new Kindle Fire tablet several times over this Christmas).

The real battle over Amazon's holiday sales figures is between Goldman Sachs and JP Morgan. Goldman's Heather Bellini turned negative on Amazon shares this week, saying ComScore data showed Americans didn't do as much shopping on the internet this year as expected – a bold call that sent Amazon shares plunging. JP Morgan analyst Doug Anmuth came out in response with a bullish call, saying Goldman was ignoring soaraway growth internationally and all the clicks from tablet computers and mobile phones that aren't counted by ComScore.

Who is right? One of these analysts is going to have an unhappy new year.