A few more things that some videos don't mention (too lazy to check jimbob's video
As plankton said, some of the connectors are tiny and rather fragile. You'll definitely want to have some tweezers ready to handle them, and watch out for the little lids and properly lift them before
pulling out the connectors.
Also be careful with the L/R buttons, they're spring-loaded (same kind you'd find in a floppy disk) and not secured vertically in any way, so it's rather easy to lose the springs when taking the case apart.
If you need to remove the wifi module (it's in the way of some cables; I'm not sure if that's necessary to just replace the touchscreen surface, I've only replaced the actual lower LCD screen, not the touch surface), be aware that one half is glued (!) to the board, so yeah, you just have to apply force to remove it (it's not that bad, just for me, who's always very careful with small electrical parts, it was rather scary).
Also make sure you keep track of which of the screws go where. The plastic is very soft, and if you screw one of the longer screws into one of the places for shorter screws, you'll likely create ugly little bumps in the case (the plastic really is so soft that you'll barely even notice the resistance before it's too late).
Otherwise I can confirm that replacing an NDS screen is very easy in general. It's a little fiddly, but there's nothing really complicated in there. Just a few too many things are secured with glue for my taste.