Sure. Let's say I'm a 1st level words of power sorcerer. I get my bloodline spell as normal, nothing special there. My spells known, however, are word spells.
So as a sorcerer I get all target words, the boost meta word, and then a number of effect / meta words equal to my spells known. I'm going to choose the wrack and shock arc effect words. Let's look at shock arc for a moment. I can cast it in a burst, a cone, or a line, or just on a single target, as a 1st level spell. Pretty flexible. I can do the same thing with wrack.
This means that the 1st level sorcerer with words of power is very flexible, right from the beginning. However, the sorcerer does have some limitations. I cannot cast either spell with the barrier target word, and the reason for that, is that I'm not capable of casting 3rd level spells (and barrier is a 3rd level word, even though, as a target word, it doesn't effect the level of the spell it is on). Another thing I cannot do is actually make use of the boost key word. Neither wrack nor shock arc have a specific boosted effect. Now the target words like burst, or cone, or line do, but that increases the level of the target word, and again, I'm not capable of casting higher level spells yet.
Now let's say I've done some adventuring and I'm now a 10th level sorcerer, still using words of power. I've gained all my bloodline spells, as per normal, but now I have gained quite a few other words. Now, I am capable of casting wrack (and shock arc) with the target word boosted (or the barrier target word), and these remain 1st level spells, despite having higher level target words (because target words do not increase the level of the spell).
Another thing I can do is cast a wrack / fog bank spell as a 3rd level spell. I can only use the barrier or burst target words on the spell (limited by fog bank), and the spell only lasts 1/round per level (limited by wrack). The spell is of both the necromancy and conjuration schools, and I can apply my spell focus: conjuration on the saving throw from the wrack portion of the spell (though the spell cannot benefit from spell focus: conjuration and spell focus: necromancy, only one or the other). Also, I can boost to increase the area of effect (by boosting the target word) or boost to be able to move the cloud (as per fog bank), or both or neither. Also, the saving throw for the wrack portion of the spell, is as per as 3rd level spell (which the spell is), not a 1st level spell (which the word itself is). It is also worth noting that because wrack does not ignore spell resistance, a creature with high enough spell resistance could ignore the whole spell (including the fog) even though the fog portion normally does not ignore spell resistance.
Now I want to mention the selected target word for a moment as it is somewhat different than the other target words. If you boost the selected target word, instead of increasing the level of the target word (as normal) it increases the level of ALL effect words in the spell. This increases the spell's level. (As opposed to increasing the target word's level which does not increase the spell's level.)
Now, if I were a wizard instead of a sorcerer, I would have had to have memorized that spell, exactly as I wanted it, with the boost(s) already applied (or not applied). But because I was a sorcerer, I was able to simply assemble the words I wanted on the fly, toss it out of the appropriate spell slot, and go on about my business. That is a HUGE boon for spontaneous casters.
And that is how words of power works. If you have any other questions about how it works, I'll be happy to answer them. The following is just my opinion about words of power (though it is fairly common).
Words of power are generally a power down for casters. If you look at the example spell: burst fire blast you'll see that to equal a fireball the spell has to have its target word boosted. Meta words (of which boost is one) are limited per day, so that is a very real draw back. There are also certain things that words of power just can't do, like say, simulacrum or wish.
There are a couple of specific (and important exceptions to that, however). The servitor word, for example, allows the casting of Summon Monster as a standard action. That's pretty powerful. (Admittedly you can only summon 1 of any given monster, as summoning 1d4+1 requires boosting the selected word, which increases the spell's level by 3 (rather than 2 as normal summon monster would do, and it takes a use of a metaword.)
Another example of a more powerful spell is undeath. It is a lower level and cheaper version of animate dead. A very, very, good word, even if you're not focusing on necromancy.
So while they are less powerful over all they do have some very good options, and thanks to their flexibility can be a very good option for spontaneous casters. They are generally a very poor option for prepared casters.
