It seems to be becoming more common here.
I'd say leave a tip if you feel the service deserved it!
I've left good tips if I've had a friendly waitress who really looked after us. I've left without leaving anything if I've had a surly bugger who ignored us for ages instead of coming to see if we wanted more drinks!
I suppose if it's one of those pub pub meals (iyswim) - not the same level of service at the table - then perhaps not. Not if it's one of those places where you order at the bar and go get extra drinks yourself etc.
I was thinking above of when I go to places where you are assigned a waiter/waitress and they take orders at the table, come to table to see if you want extra drinks etc.
Then I think it's good to leave a tip if they've done a good job.