I visited Sihanoukville for a few days over the New Year 2009 period. Expect many of the hotels and guesthouses to be full during this period. I had wanted to stay on Ochheuteal Beach, as this is the best beach, but instead had to settle on the Victory Beach area. Anyway, I visited Ochheuteal Beach on New Year's Eve to see in the New Year and the beach was packed with party go-ers and fireworks. One of my favourite photos from my trip around SE Asia is the main photo of a young boy letting off a huge, long firework on the beach - simply wouldn't happen back home!
Ochhateul Beach in particular is extremely popular with Khmers, some local, some on vacation from Phnom Penh. On the day I was there, I was the only Barang (foreigner) on the beach until a group of Germans showed up later.
Also, and this is true throughout Cambodia, the tourists you'll meet will almost certainly be European or Australian. There's always an easily identified Canadian or two (see backpack for maple leaf). But besides my friend Sparky in Angkor, I met only one other American in Cambodia (more on that later).
Why? For several reasons. First, Americans still have negative views of Cambodia as a "dangerous" country. We are not by nature an adventurous people, so we tend to stick with what we know. Second, and much more importantly, we don't have the vacation time. Americans average less than 30% of the vacation time of the rest of the industrialized world. When you only have a week to travel somewhere, going to Southeast Asia isn't worth the cost and time. I only went because I had ten days prior to beginning a consulting engagement in Saigon.
In a way, I don't mind not being able to travel everywhere at once. I met some Swedes in Phnom Penh who were spending three months in Southeast Asia and who had frankly gotten pretty jaded by the whole thing. I don't want that ever to happen to me. I want always to be overwhelmed, to be excited to get off the plane or boat or train, to mumble stultingly in a new language. I don't even the 10-month Aussies and Europeans -- they can see so much that they lose the plot.