A little correction - since Portfolio 6 there's been a menu option - File > Export Field Values.
Actually, the text export has been there since at least v4 if not earlier - I think I remember using it when I first tried Portfolio v3. The export is tab-delimited, first row being the field vames. Individual values in multiple value fields are delimited with ASCII #29 (a database standard for this purpose - that few apart from FieMaker use <g>). Hard returns inside text blacks are marked with ASCII #11 - otherwise it's just text, or rather Unicode text since late in v6's life. If you've a copy of Notepad or TextEdit you can work on it without any further tools needed. For big text exports consdier using Excel and VBA (yes, even on Mac OS) to work over the data if it needs tweaking en route to the next tool (e.g. changing MV field delimiters, etc.).
The number of records exported is the number of currently selected records in the front gallery (window) and the export dialog allows you to select which fields you wish to export (default = all fields) and even the order in which they are exported within each record (in case the next app is inflexible in its import). So in about 5 mouse clicks you can export your entire catalogue (database) text content. If you want the thumbnails these can be got out as well by exporting all records to HTML pages and harvesting the thumbnails. The previews are, unlike some DAM apps, in an external folder already. How that's not "an easy way out" is beyond me!
The same text format can be used import data as well. I regularly use text import to bring in 000,000 record sets from legacy systems and am collaboratiing on one that will bring in 0,000,000s of legacy records in a major public collection. IOW, it's scalable.
There is arguably an issue with text vs XML as the format. Ask two people, get three answers. I find that what people think is best is based on what they know and/or the tool they use most (recently). Tab-delimited and CSV text are much easier to work as even a novice can open Notepad or cut'n'paste VBA. XML is more flexible perhaps but requires more knowledge and tools the average user is less likely to posses. Personally, I'd like to see more stuff move to XML.
If you need resolve rumours about Portfolio's capabilities to actual fact, slide on over to www.portfoliofaq.com
I think the main problem with DAM is that the standards are both evolving and poorly applied. Taking a particular DAM or Creation tool and assesing the DAM world from than standpoint is a sure road to confusion and disappointment. We need to take a broader view (which is what finds me in this forum this afternoon - broadening my perspective <g>)
Hope this helps,