What's everybody's opinion about these two skills? I just started a rogue, and the game recommends raising these at every level. I've read the descriptions, but I wonder just how many creatures in the game are hidden. Will these skills protect me from sneak attacks? With the limited view range in the game, I don't see much point in being able to spot creatures at a greater distance.

here's how i rank thief skills

use magic, open locks and search, set traps, remove traps & persuade + lore (these all have high values, and get the most points)

then pick pockets. sometimes parry.

then maybe some cross class skill, disipline. (just to resist special manuvers)
maybe 5 or 10 points in spell craft (saving throw bonus)

then the sneaky skills, hide / stealth.

then finally spot and listen.

Spot & listen are pretty useful abilities...from my experience playing a ranger/rogue, I've found that the higher these skills are, the more of a chance that you will succeed in a Sneak Attack. Also, I am pretty sure that they make it harder for enemies to perform said attack on your PC as well.