If portfolio's are important to you, as the are to me (or were), don't WASTE your companies money on Acrobat 10!!! You will be gravely disappointed. Read the related posts on this forum. What's worse is I no longer have 9 on my machine, and Adobe refused to provide a download link even though I had purchased a full license!!! I was told they only have X availble for download and I would have to pay for the upgrade. So, I'm hosed. Don't let this happen to you!!!!
PDF Portfolios have changed a lot between version 9 and X, and I agree that some people love the new designs and some hate them, with equal passion. I have to say that when 9 was first released, we saw similar complaints about the styles of bundled layout; but people got used to them. Version 9 was the first attempt at this sort of thing and lessons were learned, hence the changes in X - most significantly it is now a lot easier to re-style layouts, and even write your own. Yes it still involves Flex programming to create a layout, but it's nowhere near as much a black art as it was in version 9.
I suspect that things will change again with the next version - I'm not confirming or denying anything, but we all know that there have been significant events in the Flash and Flex world in recent months. Right now, PDF Portfolios are an interesting "proof of concept" but from my personal viewpoint they never got the customer adoption we expected in the early days, especially from the Flex community. Adobe's plan was that by releasing the SDK, Flex people could make money by writing new layouts for people (which for a Flex programmer is a simple job), and Acrobat users could pick and choose from an open market of free and paid designs, just as you do now with website templates. It never happened, and I doubt it will now.
There are useful things you can do with a Portfolio that you can't do with ZIPs or attachments, and vice-versa, but the dominance of mobile in years to come will decide which methods win out. As the ISO PDF standard controls what can and cannot be put in a PDF file, doing something like switching from Flex to HTML5 for layout controllers, while technically possible in theory, would be a monumental political battle and could take several years to be adopted. Adobe may lead the market in PDF software but they're not the only player on the field by any stretch.
Acrobat Pro has always been the standard-setter for PDF creation and editing, and as part of that it is also the place where new ideas are first tried out - some, like geospatial maps, don't float and are devolved into the community or depreciated; others, like embedded video, get overwhelmingly-positive feedback. If we could predict which will work out, these forums would be a lot quieter - we'd all be lying on beaches deciding which private jet to buy.