The old opera house in Leipzig was destroyed in WWII and unlike in nearby Dresden it was not reconstructed. A modern opera house was opened in 1960. The best material that was available in those times in East Germany was used for the construction and it shows. Sure, it's the taste of the 1950s ... but still, it's quite nice. I found the acoustics to be a bit 'dry', but all in all it was fine.
I saw a performance of the ballet "Swan Lake". The soloists were pretty good, the ensemble was not really. The (Gewandhaus)orchestra played well and I regretted the imperfect acoustics. What I found annoying was that they had scheduled an intermission after both the second AND third act. Urgh.
UPDATE: In the meantime I attended another ballet (the premiere of the ballet "Giselle") with family and American friends which we all *loved* and also an opera on my most recent trip - "Il Turco in Italia" is a fun piece, very good production with excellent ideas. The tenor was unfortunately not exactly up to his task, lost his voice half way through the performance (which can happen to anyone) but the others were pretty good.
The view from any seat is good. I'd like to encourage you to buy the inexpensive tickets for seat in the back (balcony or orchestra seats, doesn't matter) - I only paid 15 Euro and was happy with the seat.
Dress Code: People didn't particularly dress up. I personally wouldn't wear jeans and sneakers, but it's up to you.
"Pfeffermuehle" is a political cabaret, which is quite famous in Germany. I had a great evening here together with VT-member Leipzig. To really enjoy the programme you need to understand German.
Dress Code: Casual
In Leipzig you find five cabarets. Here you can legally laugh at the Saxon dialect. My favorite cabaret is "Academixer". The word "academical" gives the Academixer its name. Founded by the students Christian Becher, Gunter Böhnke, Jürgen Hart and Bernd-Lutz Lange in 1966 it has become one of the most popular cabarets in Leipzig.
The Gewandhaus is a modern concert house on Augustusplatz. The main foyer is dominated by Europe's largest ceiling painting. The Great Hall offers seats for 1,900 persons and is dominated by a giant organ with over 6,600 pipes. The Mendelssohn-Hall offers around 500 seats and is also used for congresses.
The Gewandhaus offers around 800 events each season.
Dress Code: dinner jacket/ formal dress
We went to the opera in Leipzig, it was easy to get tickets on the day itself and they were not very expensive. We saw Mozart's 'Marriage of Figaro'. The voices were marvellous, the setting was modern which took some getting used to but was effective.