1000 feet is a fairly long way apart (in fact its the normal vertical seperation, but as this is classed as an airprox then I guess you mean they were laterally seperated). The severity of the incident is dependent on a number of factors including relative tracks of the aircraft, closing speeds, whether the aircraft were visual with each other or not, etc etc. As none of these details are in your initial post its rather difficult to comment. Airproxes are rare in the UK and flying is still the safest way to travel by far. That said I have no doubt the media (and that includes the beeb) will be reporting the 'near death' experience of these passengers tomorrow regardless of what we say here. After all "HUNDREDS CHEAT DEATH IN JUMBO NEAR MISS - PILOTS IN PANIC DEATH DIVE - more bad news for troubled ATC centre - is it a gypsy curse?" is a lot more news worthy than "Rare loss of ATC seperation reported over Wales. Both aircraft continued safely to destination"