There really is no comparison. Google Docs for the price, versatility, options and features is hands down the ultimate suite of technology and tools for your business. Granted, Microsoft Office has features that are not available in other online services like Google Docs, but the reality is that 80% of what you do in business is already web-based.
Once you've taken the time to explore Google Docs, share and collaborate with others on Business projects, and experienced the freedom of accessing everything you do on-line from any computer, anywhere in the world, you'll see why Google Docs is the only way to go with your Web 2.0 Business. It's good today, but with all the support and future enhancements and developments, it'll even be greater tomorrow!