Build a Website for user generated video content similar to YouTube

We need a site that will have most of the basic functionalities of YouTube. The look and feel should be like YouTube The site must include; User log in User channels Playlists Landing page with categories/playlist Monetization capability - connections to video ad servers/networks The code must be owned by us or on open source license. It may use a platform of your choice. Preferred PHP or .Net base, but not necessary. Additional features a plus; Instant messaging Will prefer companies that can show a prior product similar to these requirements.