PDF is ok for document presentation on the web, the market penetration of Adobe Reader is pretty high. That said, if you don't want to deal with the ridiculous bloatware that its download entails, there's a smaller, lightweight pdf reader called FoxIt, which for 99% of people is perfectly fine.
Another interesting option is FlashPaper, allowing the export of documents to Flash. The number of people who don't have the Flash player plugin for their browser is miniscule, since it's practically essential for viewing large numbers of sites these days.