I have had none of the problems that other reviewers have noted with Adobe Reader 9.0. It installed and operates very well on my 2 GHz 1 GB Intel MacBook running OSX 10.5, even with other applications, such as Pages and Filemaker running. I have noticed two areas in which the Adobe product outperforms Preview; but I agree with other reviewers that it would be hard to find many killer advantages over Preview.

The significant differences that I have noticed so far are:

- Adobe Reader 9.0 requires 251 mb of hard drive space -- more than 3 times what Preview occupies -- but it certainly doesn't deliver three times the features and functionality.

- For people who rely on, or prefer to use, speech capabilities, Adobe Reader 9.0 is the better choice. Preview was able to read a 33 page PDF document with highly technical language fluently -- even while doing a Time Machine backup. Curiously it flubbed some very simple everyday English words. Adobe Reader was very slightly better in terms of speed, but substantially superior in terms of accuracy. It read the same 33 page document with no errors whatsoever.

- The non-functional menu choices in Adobe Reader 9.0, which require other Adobe products, are annoying; but Reader is, and always has been, essentially a marketing product for Adobe. I can forgive them that.

- Adobe Reader 9.0 provides a little more flexibility in printing documents than does Preview; but I would probably need to use Adobe Reader 9.0 for printing a PDF document, rather than Preview, not more than 5% of the time

I am going to keep Adobe Reader 9.0 on my machine, but I cannot envision many situations when I would use it rather than Preview. Like most Mac users, I doubt that I would be hooked by Adobe Reader 9.0 into considering other Adobe products, but it is worth keeping in the Dock.