It's good to see these new multi-million pound matrix signs doing something useful, rather than either handing out pointless or even incorrect information (the favourite being 'queue ahead' when you're already in standing traffic) and being used to digitally patronise drivers ('fasten your seatbelt', 'check your fuel' etc.)
The article says they've been trialling this in the West Midlands, but they've actually been running it on a good stretch of the M6 for several months. I've noticed they've got some of the matrix signs on the M62 doing it as well now, though the timings have to be taken with a pinch of salt - my 10 minute journey to the M6 took me 14
Not that I'm complaining - the speed of traffic is going to vary and the signs can only ever be taken as an indicator. I reckon it's a great service, and it's good to have ANPR being used in favour of the motorist instead of against us for a change.