This sounds very true - I think that we're going to see a two tier market in which every real brand has to own their .com - as long as Facebook, Amazon, Google use .com as their flagship tld they will remain must-have properties.
Everything else is just on a nice-to-have campaign specific basis. The domaining market therefore will exist to sell wannabe big brands the .com they want (or typo variations). Existing brands will just sue you for it of they have to.
It will be acceptable to run a non .com, so many quick-hit sites (ecommerce startups etc.) with no major brand aspirations will be happy with poker.chips type domains as there will be less expectation on them owning a dot com (unless/until they get big).
Therefore .co.uk will cease to have much resale value within 5 years I bet - well, it will have value if someone really wants it but no default value.
If I owned a lot of .co.uk's I'd be having a fire sale.
If and when Facebook etc. abandon .com the game will change again but I can't see that happening in the foreseeable future.
What a load of twaddle
How could you know what you would do with a portfolio of co.uk's if you had them, you don't have them, have not grown with the industry, so couldn't possibly know what you would do. One thing is for certain though, if they were anything like beforeyouinsure.com which you have, it would be no good having any kind of sale because they would have no value in the first place.