I just returned from a fabulous nearly two-week vacation in Cambodia. This was my first trip to Asia, as well as my first trip to a developing country, and as such it was quite an educational experience! We visited Battambang (the second-largest city in the country), Phnom Penh, Kep and Siem Reap, where the temples of Angkor are located. As we traveled across the country by taxi, boat, tuk tuk and moto-dop, we kept remarking to each other: This is a country with huge potential. The people are friendly, the coast is simply gorgeous, the food is delicious and the cultural heritage in form of many temples widespread. Of course, there are things to get used to (dust, dirt, trash in the villages, lack of electricity and hot water in Kep (but it is coming soon!), lack of potable running water (but everyone sells bottles) bugs, heat and humidity), but the benefits far outweigh the discomforts. And everywhere you go, they are building building building.
Tourists abound in Phnom Penh and Siem Reap, but once you get outside those places, they appear only in small numbers. In the villages, the little kids wave, smile and say "hello" to you as you pass by. There are signs everywhere of the tragedies of the late 20th century, from abandoned villas to demining crews, to people with no hands and feet. The killing fields are now tourist destinations, and many people are happy to tell you their rather gruesome stories for a few riel. It is a bit disconcerting to realize that the government hasn't really dealt with this past, and the former Khmer Rouge live side-by-side with their victims. And, in fact, many of them became victims themselves.
Overall, I would highly recommend anyone to visit there. We did not go with an organized tour group, and if you don't want to do a lot of negotiating at taxi stands among mobs of drivers, you might want to go the more organized route. I admit to some second thoughts as we negotiated the border crossing from Thailand (we flew into Bangkok and took a 3-hr taxi ride to the border) to Cambodia at Poipet (first time I walked across a country border!). But if you are willing to risk a bit of adventure, heading off on your own is perfectly safe and a great deal of fun. Be prepared for everything to take longer than you expect however. Sometimes the negotiations for the taxi took nearly an hour as we negotiated in three languages (English, French and Khmer).
I'll post some pictures on Flickr in the near future and will give you the link when I do so.