I recently purchased this and watched it casually all the way through, and plan on watching it many more times while actively following along in Terragen. So much content to absorb!
The first video which is the "Friday Session" from Jan. 18th 2013 is 1hr 35min and is like an award presentation (TOSCARS) of the best Terragen work by many of the artists on this form. It's great to hear some of the voices of the people we know on here, and see their best work.
The second video is the start of the "Saturday Sessions" and is 58 minutes. It's hosted by Oshyan, and is a great beginner overview covering the Terragen 2 interface, basic workflows, the Library, Object Populations, Nodes, Rendering etc.
The third video is the continuation of the "Saturday Sessions" and starts with a 1hr 50min segment hosted by Martin Huisman (Tangled Universe / TU) and is more intermediate to advanced. This is where a beginner really needs to start paying close attention. I learned some important differences and uses for the Compute Normal, Tex coords from XYZ, and Compute Terrain nodes that TU really made clear. He teaches you how to make cracked surfaces on your terrain, strata and outcrops, using the redirect shader, power fractals, Voronoi, Fake stones etc. Lots of Terrain detail work!
After about 1hr 51min there is another presentation by Frank Basinski on Clouds & Atmosphere that's 1hr 30min long. Lots of tips and tricks for making great looking "Monster Cumulonimbus Clouds" and he covers sunsets towards the end.
The last video was the "Sunday Session" and starts with a 1hr 50min segment and is hosted by Martin Huisman as well. You will learn about Importing trees/grasses, object population placements, masking populations, managing population sizes, tweaking populations appearances, tweaking object shaders, and rendering. The second segment of this video is focusing on Ron Miller a Professional Illustrator & Author. Lots of inspirational artwork, and discussing of techniques he used.
I thought it was well worth $49.