Well still a relatively inexperienced player, I can offer some insight:
The bakka list from faq 2010 offers almost no attack craft, but compensates with high turret rating capitals and strong direct fire battleships and battlecruisers. They have a few unique escorts that are actually quite good, both as gunboats and torpedo destroyers. It also has easy access to AdMech vessels, which if grabbed with fleet defence turrets can really help with the lack of AC.
The armageddon list from armada gives the additional bonus of easily accessible battlecruiser, albeit only two varieties available. It has a large variety of vessels, and due to the lack of fast ships tends to be slower and more defense oriented. This can be mitgated by taking advantage of the fact that you can also include space marines with very little restriction, making this a very strong list.
The obscuras bastion list from armada grants easy access to grand cruisers, along with all-around access to a good selection of other cruisers, making it a good line fleet due to double grand cruiser core. The reserve fleet is somewhat more limited in selection but adds several chaos ships to the list, along with some minor disadvantages when you pick them.
The gothic list restricts you to the core vessels, but that's it. It also allows you to run dominator's and dictators in the same fleet, which for some reason is not allowed in the other lists.
The BFG:R lists include a almost direct port of the obscuras and armageddon lists, but introduces a warden list. This list is supposed to represent a self-sufficent mobile patrol fleet on the galactic border, and thus features lots of light cruiser, backed up by ordnance cruisers and escorts, with battleships and grand cruisers rarely seen.
More mobile and ordnance-erific than typical IN, but generally weaker in direct fire, with distinct lack of nova cannons.
Truly veteran players can probably shoot these generalizations down, but these are accurate as far as I know.
