I'm no pro reviewer, so I will keep this relatively short: This PDF is very good, but very imbalanced.
The pdf contains a feat that allows you to modify skeletons with special tricks they can do. All the tricks have a prereq of certain skills (common), feats (uncommon), and in at least one case class features to use.
Some of the tricks in here are spot on. For example, gold plated skeleton lets you put 500g per HD worth of treasure onto the skeleton to give it +1 AC/2 levels. The treasure falls off when the skeletons die. Similarly, spinning skeleton lets the skeleton take a full round action to effectively power up his attack by pivoting at the hip, letting him use power attack: hilarious, and in certain situations effective.
Others are there, but lacking things needed to make them balanced. Scrolletons lets you make skeletons into scrolls, casting the scroll destroys the skeleton. The scrolls max level cant be higher than the undeads HD. Several things are missing here though: do you pay for the scroll normally? Where does the skeleton need to be in relation to you to use the scroll? Can the skeleton activate his own scrolls? I suspect the answers are pretty easy to reason out, but it shows the lack of thought that went into some of these.
Then you get to some that are just straight up overpowered, especially given that only a few of the tricks list costs associated with them. Ironbones gives them a +5 to AC. The bonus is typless, and since its free theres no reason not to give it to every skeleton you ever raise, and even stacks with gold plated skeletons.
The piece de resistance for this category however is Wand Skeletons. It allows you to craft a wand into the skeleton, and then retrieve it at any time destroying the skeleton. By itself, this would be no big problem, and matches a few other similar abilities to store swords etc. Unlike every other "hidden cache for storing x" skeleton, this one both explicitly states the skeleton can use its own item, and the skeleton isnt destroyed for doing so. The command to make the skeleton start blasting with its wand is a move action, meaning you could give two such commands a turn. If that wasnt strong enough, the skeleton will continue mindlessly blasting shots at the same target with its wand every round. Thus, you can continue commanding 2 skeletons to add their wand blasts (say, of magic missile) to the fuselage every round. They even stop firing if the target dies or moves out of range, so no worry about wasting charges telling your army to stop.
All in all, most of the modifications are fine, and very fun to boot. Theres a few in there though that will require some DM oversight to prevent cheese however.
The books title and description is Skill Talents, but these are actually Knowledge Talents as there are no talents in here that are not Knowledge based, which is highly disappointing. The concept has been done before and those other books have alternate uses for all skills, and besides that the power of some of these talents are on par with low level utility spells, and often cost only 1-2 skill ranks.