Congratulations!!!

I tried to collect some information for you:

number of flights/aircraft:
- daily from CLT to MUC with A343 with new business class [dep. 17:15]
- twice daily from IAD to FRA [dep. 16:20 with A343 with old business class as far as I know; dep. 18:10 with B744 with new business class]

seat configuration in business: 2-2-2 on the A343 and 2-3-2 on the B744 (with 2-2 in the front/nose)

connection in MUC: MUC is very very comfortable for connecting passengers, very short waiting times at passport control, good shopping possibilities, modern architecture, connections to FRA every 60 minutes, nice city (if you like to do a stopover), etc.

In the end, you have to consider how easy you can get to IAD instead of CLT. If I lived near CLT, I'd take the connection in MUC and make a stopover as it's quite easy to go from the airport to the city by public transportation (arrival in the morning from CLT, departure to FRA on the same evening might be an alternative). If you don't like to make the stopover, it's still easier to connect in MUC instead of going to IAD.
But please make sure that you'll be on the new business class under any circumstances when crossing the pond because there are some heavy differences between the old and the new seat while the service is the same.

What to expect of LH's business class?: a good seat (if it's the new one) featuring an angled-flat position for sleeping; solid service (three courses for dinner + breakfast on CLT-MUC, three courses lunch + afternoon snack on MUC-CLT); lounges with basic snacks/drinks and sometimes showers (better than UA's RCC but nothing like SQ's or TG's business lounges), nice audio/video on demand with good movies

To conclude, don't expect the best business class product on earth, but it's usually better than business class on American carriers.

Alternative: You could also take the nonstop flight from CLT to FRA with US Airways if your tickets are valid on all Star Alliance carriers and you don't mind flying with US Airways.

I hope that helps for the moment.