I am currently (Aug 27, 2013) working on this terrain tutorial. It's difficult to project exactly how long it is going to take to finish the terrain tutorial (and get back to finishing some of the earlier tutorials.) But hopefully, the terrain tutorial will be done over the next month or so. I'm working on getting the tutorial code finished before writing the web pages. That way I can at least get the code where you can download it.
This is going to be a multipart series on game terrains. I think I am currently about half way through Part II and this is my top priority right now. Part I will likely cover creating the terrain grid, collision, and fault line terrain generation. Part II will likely cover creating a terrain game component, centering the terrain, using photos as height maps, further optimization of the code in Part I, and texturing the terrain. I'm not committing to what is exactly going to be in each part, but that's what I'm thinking at this point. After that, there will still be much to cover, such as ROAM and incorporating the skybox. This is likely to be at least a four part series. I am hoping to get Part II on the website this weekend.