Hi there,
Just back from Krakow, was there for 10 days. Had a good time but 10 days far too long definately a long weekend destination. Weather was great, food was great and everthing so cheap. Went to the Wieliczka Salt Mine, Auschwitz-Birkenau and the fantastic local zoo all were brilliant. We used public transport to do all the trips but did not find it easy to get info on times of buses/departure points etc luckily we had purchased a decent guide book before going. You can do organised tours but quite expensive and unfortunately dont bother going to the tourist info offices dotted about as they have next to nothing in English. One thing to buy is the latest copy of 'Karnet' which has some things in it in english.
Also try and take in the Krakow Tour Bus which you can hop on/off all day.
Never had a bad meal-food was really good. All the restaurant/bars we went into were great including The Bull Pub,Nic Nowego, Poz Zlota Pipa, Sioux Steak House, Piccolo Mondo, Restaurant Wierzynek and Pod Krzyzykiem to name a few and then there is lots more great places in the Jewish quarter.
Only downside to the holiday was that I found a lot of the polish people were quite ignorant/arrogant and never crack a smile. Have travelled to other countries where the locals dont know much(if any) english and i dont know much of theirs but through a lot of pointing and hand gestures you get there with a few laughs thrown in.....but no chance here in krakow....they look at you as if you have horns coming out your head. One last point was that there is quite a lot of begging(from young to old) in the streets and also coming up to your table while your eating.
Certainly would say go if you get a chance but only for a long weekend. Also, get used to getting stared at and not seeing a smile on anyones face.