Rating: - Easy to Use, Expansive Product Suite
Office 2008 is much what it is advertised to be: it is fast, flashy, and overflowing with ways to get your work done. From installation (which is more like a windows installation) you can pick and choose which products to install - I don't use Entourage, so this review ignores that product - it was very simple to exclude from the installation.
It's hard to escape MS Office these days, and though Apple Pages can save documents in Office readable formats it is a process at every save that you must go through - this isn't a Pages review, but I have used the Apple productivity suites, and I must say I prefer Office 2008 and not just for compatibility issues.
Don't be fooled, there are some problems with Office 2008 - the graphics are very nice and there are numerous views to organize and create Word documents in - the cost is that these graphics do not always work correctly. Problems occur especially when multiple windows are open, and Office reacts strangely to OSX Spaces - the main Word window will shift spaces when cycling through programs, and the toolbox has a strange way of dispersing itself across the Spaces - press f8 to bring up all open spaces and you can quickly locate the fragments of the toolbox and by dragging them, reassemble it - a simple fix that can become time consuming (say if you like using the internet and iTunes in different spaces) and it's something that shouldn't have to be fixed in the first place. In Word the cursor has a way of disappearing after switching Spaces and if it becomes visible again, well lucky you.
Despite these flaws there have been some significant improvements. These are of course similar to those witnessed in Office 2007 for PCs - bright graphics which replicate the menus of yesterday for doing such things as changing the style of your paper, adding word art, charts or virtually anything else you may want to do. These are again replicated in the toolbox - giving users at least three ways of accomplishing the same tasks (menus remain largely intact).
These changes make for a more customizable workspace, and much quicker access to various different functions of Office 2008's various programs. Things that even an experienced user may have once passed over are obvious and easily inserted quickly and without fuss (hyperlinks in Power Point are extremely easy, and provide thumbnails of slides for easily linking slides together). It doesn't just look good, it truly is useful - what really is simply a cosmetic change, is surprisingly helpful.

So - in conclusion Office 2008 works faster, is reliable (never had a crash, always opened documents, works great with other versions of the programs - older versions still open and edit 2008 saved documents), is visually appealing and quickly provides its entire expansive list of features for users. Unfortunately it is completely ignorant of Spaces, and as such may become more of a headache than a blessing for anyone that uses spaces (pretty much at all - changing spaces leads to erratic behavior - writing this review I changed a song in iTunes and literally lost the Word window!).
I would recommend buying Office 2008 - it has a lot of features, it is easy to use and can create some very nice looking documents and presentations. If the spaces get annoying, and you don't use or need all of the features then try Apple's Pages and Front Page - it has a lot to offer, but not quite as many features.

---

Rating: - Not a good dollar value.
The primary reason a lot of people buy Office is simply to be compatible with other Office users, but this version _isn't_ very compatible. MS omitted VBA from all the 2008 Mac editions, and the home edition further lacks Exchange Server support (making Entourage pretty much pointless), and the data analysis pack for Excel.

Backward compatibility is not terrific either, and no I'm not talking about the switch to OOXML file formats. I have a number of "legacy" files and templates that were originally created with Office 2000 and XP on Windows. They open fine in Office:mac 2004 and Office 2003 for Windows. The even open with iWork and OpenOffice. They do _not_ open properly with Office 2008 or 2007. (This won't be a surprise to longtime Office users. Swapping files between old and new versions has never been completely painless.)

So with compatibility with other Office users all but removed from the equation, it seems to me there's little reason not to use one of the cheaper, or even free, alternatives to Office. Apple's own iWork is really slick, and costs about half what the Office home edition does. NeoOffice and OpenOffice will keep even power users happy, and they're _free_. By comparison, MS Office is sluggish in operation, and doesn't bring enough to the table to justify its high price.

---

Rating: - Office 2008 for Mac
I have been using Office 2004 for Mac for the past few years. I decided to switch to Office 2008 due to compatibility reasons with Vista. 2008 is very similar to 2004, although it does offer some more advanced features. In terms of using applications, most applications have the same or a very similar layout. Although I don't think it is completely necessary to upgrade, I would recommend Office 2008 for Mac anytime. If you are interested in purchasing 2008, I believe there is a video on apple.com that explains all of the new features.

---

Rating: - Excel Does not work
Word and Powerpoint seem to work OK, but Excel is so slow as to be worthless.
I have a brand new Mac Air, and I did get all the updates, and I tried resetting file preferences.
I have Parallels, so I will be installing Office 2000 on the Windows side of things so I can use Excel.

---

Rating: - Incompatible with Spaces
I would love to be able to stop using MS Office. Unfortunately, collaboration at work requires that I use Word 2008. Word 2008 is completely incompatible with one of the features of OS 10.5 that I use the most frequently, Spaces. It's been over 6 months since Office 2008 was released, and Microsoft hasn't fixed this bug. Ridiculous.