On Thursdays and Sundays go to Soda Club and on Friday and Saturday to Havanna. Havanna has three dance floors, one only for salsa.
Soda Club is in the Neue Kulturbrauerei - Knackstraße in Prenzlauer Berg. Havanna is in Schöneberg.
When we were there last August, DJ Ronny played in Soda Club and on Friday in Havanna. He was a great (!) DJ and we danced until we dropped. We did not like the DJ on Saturday in Havanna, but that is a matter of taste, I guess.
This weekend Ronny will be DJing on the salsa boat in Offenbach (Frankfurt) and, of course, we will be there!
Here is a late entry for a question from 2005 but if someone is interested: the best Salsa club in Berlin is by far the Soda club. Thursdays and Sundays it is amazing. You have 4 floors:
1. Mambo Club in first floor left
2. Kizomba in first floor right
3. Cuban style in second floor, front
4. Bachata in second floor, behind
Many people on a Thursday night. It starts at 7pm with introduction classes but I recommend to come at 11pm. Stay until 2am if you can afford a late night visit of a club in a work week. Check it out.