Stop in Bamberg?

Bamberg is just 45 minutes north of Nuermberg by train, so it is not a huge detour by any means.
By next October, I assume you mean 2017. So you are doing long range planning. I'd consider flying into Munich as you might be able to get a non-stop (again assuming you are coming from North America). Salzburg is a small regional airport so you would need a connection from somewhere in Europe to get there. It is a pretty easy train trip from Munich airport to Salzburg with a train change in Munich.

It's possible but flying into Salzburg on a Wednesday then taking the train to Bamberg on Friday then train back to Nuremberg on Saturday is not what I call relaxing. It's not likely you will have much time for anything other than trying to stay awake on Wednesday so that only gives you on full day in Salzburg before you are off again.

Is there something in particular about Bamberg you want to see or are you just trying to squeeze in one more destination into your trip (I completely understand the latter)? If you are just trying to squeeze in another destination I'd suggest stopping in Munich on your way to Nuremberg or the lake district just south of Munich as a second stop instead of Bamberg. It wouldn't add any more time that Bamberg.

DJ

Thank you both. DJ--I just found online that Bamberg is a hidden gem, but I think you are being the voice of reason. We would like something picturesque and romantic heading into the busier cruise (Nuremberg-Regensberg-Passau-Krems-Vienna-Budapest), and it sounds like Salzburg should be perfect for that.

My question is: Is it worth cutting our stay in Salzburg short to spend a night in Bamberg? Without that stop, we would just spend Wednesday, Thursday and Friday in Salzburg and then train to Nuremberg Saturday morning via Munich.

If you have to go to Nürnberg anyway it would save some travel time (and probably money) to fly into Nürnberg (or Frankfurt or Munich, resp., and train to Nürnberg) and to visit Nürnberg (historical city, nazi documentation centre), Bamberg, Rothenburg o.d.T. and / or Würzburg.

Nürnberg, Bamberg, and Salzburg. Bamberg is close to Nürnberg; Salzburg is the outlyer. I'd skip it and spend more time around Nürnberg. You should definitely spend some time in Nürnberg itself and see Bamberg and Rothenburg, maybe spend a day in Würzburg.

Save Salzburg, along with the Salzkammergut and Berchtesgaden for another trip.

I was solo in Bamberg for 3 nights last week. It had been on my list for a couple of years and I'm so glad I finally got to make it there. If you like beer you'll be in heaven! Rent a bike and you're on your way! I can't speak to it on a honeymoon-level but I had a fine time!

We did a Bamberg 'brew crawl' a few weeks ago - they supposedly have more breweries per capita than anywhere in the world. (I may not have that statistic right but it has a lot!) we had a blast but then again our motives were largely based on visiting 8 of the breweries in a day (I had to stop sampling at brewery #4 - there's only so much beer I can handle!)

Bamberg was nice, but I liked Rothenburg a lot more for the ambience and its medieval quaintness.

I spent three nights in Bamberg last year and loved it! Every day there was some entertainment under the covered bridge, the historic center is great.