More well known may be the city of Guilin which hosts the areas main airport and is approx. a 1.5 hour taxi ride away from Yangshuo. The entire area is known for it's amazing landscape - seriously, just beautiful! - it's covered with mountainous karsts, which are limestone "mountains" and are just amazing to look at. Yangshuo area is still pretty low-key, there are quite a few Chinese tourists that go to see the karsts as well as a very well known light show called "Liu Sanjie" - for more info click here - that is performed on the Li River (yes, literally on the river.)
Other than the light show, most people go for the outdoors activities in the area like; Rock Climbing, Hiking, Biking, Hot Air Ballooning, Cave Tours, and probably the most common Bamboo Rafting. You'd probably need at least 3-4 days to do and see everything, but if you're just looking for a weekend trip out of Shanghai for some fresh air 2 days is fine. We stayed at a fantastic little hotel outside of "downtown". It's called the Li River Retreat and is set up on a hillside overlooking the river. Fabulous place!
Some photos we took are below - some are from on the ground and others are from the Hot Air Balloon ride we took which was an all together amazing experience just on it's own.
**I'm having problems loading pictures...I'll post more later...sorry!