A good view. Some of these concepts came up in a ski thread, so for those who might be curious but haven't done a pumptrack or dirtjumped, and feel they are past the point of trying this, this is a decent mature-guy summary. I do think some of the jumps still look beginner-unfriendly. Most places will in fact have beginner-friendly lines, assuming you already have good fitness and good basic bike-handling. The 24"er is also a great thing for many to consider.