Pingyao streets are narrow and are made of stone. It is best to buy a map so you won't get lost. While walking around you will find streets filled with shops, snack vendors, and restaurants. The original architecture also houses local homes and temples as well. It is a lively place with local shows and street performances. You can buy an all inclusive ticket that allows access to the local tourist venues and the city wall. Other venues are located outside the city walls.
A "must see" when in Pingyao is the "Impression Pingyao" show. The show highlights the city's people and history. It is an interactive show that I enjoyed very much and will never forget.
The food was also very delicious and I highly recommend the Pingyao beef dishes. You should also take some dried Pingyao beef home with you.
We also went spent an afternoon in Taigu, another ancient city between Taiyuan and Pingyao. It is also an walled city and is the twin city to Pingyao. However, unlike Pingyao, Taigu is not commercialized and the city has a more authentic feel when walking around.