Well, MJ, there's nothing like trying it yourself.
I can't say I played much with any of them, least of all keynote, but here goes. Pages seems about the same as the previous one. The only difference I think I noticed was footnotes, which I don't think was there before. Still, not for academic writing, unless you like doing stuff manually. They should really open their app for reference-managers like Mellel/Nisus/Word does. At the same time it's fine for most other docs and I hear it integrates well with Numbers.
Numbers, my first take, seemed pretty simplistic. And it is. What I like about it though is the templates, which are a great boon. Say you want to do a valuation, an invoice, or whatever. Much of this is already there for you, saving you some time and looking pretty. I like that A LOT and expect there to be more templates later.
Keynote, I haven't really looked at. From what I've seen, I think there are some nice templates and I like the export-options.
As it appears to me, Apple just offers a package for people that want to get to a result quickly. That narrows down the paths you can take, but it also makes some of the tedious chores easier. I hate excel, yet I have to work in it. I'm hoping that in the future, that will no longer be the case.
All I can say is try it yourself. You'll need 500 mb to download and 1.1 GB to install it, but you can always remove the apps you don't like later.