Do Jobs complement one another as in FFXI?

In FFXI, you could have a main class and a sub class. This could lead to some pretty amazing and pretty terrible combinations. You could create a super tank that could take anything the game would throw at it, or a hyper-agile character that could never be hit. Or you could create a white mage with a bronze dagger. :roll2

Does FFXIV work in the same way? I've been reading BoB's posts a lot on this, and it seems as though you have greater control over what type of character you're going to play as, though this leads to less specialisations. Can you still combine certain classes to make a really powerful class, or does the game simply allow you to benefit from all the classes you level up in?

Not exactly.

There are two seperate things you have to know first - classes and jobs.

A class is something that is more suited to solo battles (or small parties) and is much more customisable. When you reach certain levels with certain classes, you unlock jobs, much like in FFTA. For example, if you have a level 30 Gladiator and a level 15 Conjurer, you can unlock the Paladin job. A job is something that is much more suited to party play, being more specialist than the classes are. Note that the job is tied directly to the 'main' class that unlocked it - in this case, it's Gladiator. When I level up my Gladiator, I level up my Paladin, and vice versa. They share experience bars.

Regarding the levels of customisation...
Classes: On my L50 Gladiator, I automatically get access to every Gladiator action (ie, ability or spell). There are 15 of these. I can also use up to 10 different actions from other classes, too. So I could have 15 Gladiator skills, 5 Pugilist skills, 2 Marauder skills, and a skill each from Conjurer, Thaumaturge and Archer.
Jobs: On my L50 Paladin, I automatically get access to every Gladiator action. There are 15 of these. I can also unlock a further 5 Paladin actions. On top of this, I can also use up to 5 different actions from either Conjurer or Marauder (ie, I can not use Thaumaturge or Pugilist skills, etc).

Hope that makes sense. Any questions? :p

Hm, sounds more like a DQ job system than the traditional FF. Seems like there would be a lot of possible combinations based on the skills you choose!

Sounds confusing, but interesting! I'm getting more and more excited to try it out!