Actually I prefer the Spatenhaus. Much more civilised. Also try the Nuernberger Bratwurstgloeckl (near the Marienkirche) for the best sausages.

Another vote for Munich and Augustiner, was there last year during Christmas time and it was great. You will not go hungry or thirsty plus it is beautiful during the holidays.

I would also recommend the Deutsches Museum which a museum for Science, Technology, and Engineering. It is huge and has a lot of cool exhibits, really enjoyed the handful of huge rooms dedicated to aviation.

Of course, since you're not going until December there's still plenty of time to order that BMW on the European Delivery program and get a free day at the Welt. Your savings will pretty much pay for your entire trip!

And a vote for Munich from me also. I haven't been to Christmas markets in either city but have been to both cities on other occasions and much, much prefer Munich. Actually I just spent a horribly boring, rainy Sunday in Frankfurt and promised myself that I will not return for a long time.

Hahaha this is exactly how I plan to justify buying a new BMW and doing the European delivery program!

I've done it - don't accept their 7% off offer. You can get European Delivery Invoice (not retail, invoice) price plus $750 to the dealer. I got mine for between 11 and 12% less than US dealer price.

This.