Is this the joke thread? I mean, you guys are kidding, right? A Nikon is hard to load? The early Nikons (pre-F100 and its autoloading ilk) are no harder to load than any 35mm camera. bblhed has a good suggestion about the rewind lever; I have always done that, and it does give a visual proof that the film is properly loaded.
But the best tip I ever heard was from a Pentax rep. Basically, he said to reverse the loading instructions: first, holding the open camera in your right hand and the film casette in your left, insert the leader into the takeup spool (yes, BEFORE you put the film cassette into the camera); then turn the spool with your thumb, wrapping the film around it securely; THEN pull the cassette back over to the left side of the camera and drop it into its place. Take the slack out with the rewind lever, close the back, and fire off a couple of frames... and you're done. Once you get the hang of this "backwards" technique, it is very fast and secure.
In spite of the Leicas' reputation for difficult loading, the M4 and later are really quite simple, especially if you use a wrist strap screwed into the base plate. Hold the camera in your right hand and remove the base plate, which will safely dangle from the strap on your wrist. Invert the camera, flip open the back window, insert the film cassette, and pull the leader across to the takeup spool, inserting it between any two of the three "fingers". Put the base plate back on, fire off two shots, and start shooting. The earlier M's are more difficult because you have to remove the takeup spool. But the wrist strap on the baseplate still helps.