PS3 and UK are good keywords but the Sales isn't so great when suffixed on the end of this 3-word domain. The .co.uk is okay and works well if you are going for the UK market with this although .com (PS3Sales.com) would have been better for global use and would have improved the overall value of the domain name itself.
A Google search for "PS3 Uk Sales" (in quotes) brings up only 12 results (and some of those are about your domain).
An Overture search for PS3 Uk Sales shows no results. The overture for PS3 UK shows 170 searches, and PS3 Sales shows 3232.
The Overture rating can probably be attributed to the fact people were searching for information about the number of PS3 sold at launch etc... this keyword combination will no doubt die down after the console has been fully launched worldwide.
Taking the above into consideration, and the domain name extension (.co.uk), I would value this domain at v.low $xx now, and regfee after the UK launch as this keyword combination becomes increasingly unlikely.