I think it does depend on the company, if it is 100% web based .com seems to the best bet, if the web presence is more bricks n clicks and the company is uk based then .co.uk seems to be better.
We have a client that provides enterprise training, they already had a .com domain but because most of their clients were within 50 miles of their base they were typing in the company's name and .co.uk
For those who compete in 'global' markets, like yours matrixx, the .co.uk gives a geographic definition for users, from my experience this puts off USA buyers, they start thinking in terms of 'GMT'. Of course with all of the geo-ip services it's now really easy to serve up pages based on the users location automatically - send the uk visitors to .co.uk and the rest of the world to the .com
Back in 2001 I started a VPS service under a .co.uk domain, the customer base was 40% uk, whereas, for our normal hosting, under .com, the uk base was 15%. When I changed the vps service to both .com and .co.uk (but .com as the main) the uk base fell to around 20% but sales quadrupled. But that was a hell of a long time ago and things have moved on a lot since then. In those days the USA thought our ISP services ran on string and tin cans and assumed that if it was a .co.uk the servers were in the UK. Now having UK based servers is a premium.
Of course for brand protection it's probably wise to have .com and .co.uk otherwise some joker may try and piggy back on your success. I had that problem back in 2000 with Blue Box Internet when all of a sudden Blue Box xxxxx sites started springing up, so it cost me around $200 a year just to keep all of the relevent .com .net .co.uk names