No, as TimmyDax pointed out, you need to own an Apple device. You can't just open up a free iCloud account and start editing documents. This is a significant impediment to iWorks becoming an open standard for collaboration in the way the Google Docs is.
My point is that iWorks will still not be good for open collaboration, because it will only function for people who own Apple devices. So, Apple still does not have the ubiquity of MS Office, and it doesn't have the "it works everywhere for free" aspect of Google Docs, and so iWorks is still not going to gain any significant penetration. It's fine for those who use it, but, most people won't.
As a long time Apple watcher, I've seen this over and over again. Apple makes a big deal out of some software package (HyperCard, AppleWorks etc), then a few years later it lets it slide. Then the package is forgotten and all the users are SOL. Apple is not a software or a services company. Apple is a hardware company in that it's business model is designed around making money from selling hardware. Apple ultimately does not care if you get annoyed with them because some application package they sold you isn't being updated or is missing features. As long as you keep buying their hardware, you can complain all you like. In this way, their software only needs to be good enough to keep you buying their hardware. I think the one case where this is not true is the OS. Apple does view the OS and the hardware as being almost one-in-the-same. They make great operating systems. Don't use their applications if you can avoid it.