The Leonid radiant at 04:00 UT in the UK on the morning of November 17th looking southeast.
In 2012 the Moon is new at the time of the Leonids maximum, setting early in the evening and not interfering with viewing the meteor shower.
Leonid meteors appear to radiate from the head of Leo the lion. The result of particles shed by comet Comet Temple-Tuttle burning up in the Earth's atmosphere, the usual maximum is around 15 meteors per hour but a stronger storm might be seen every 33 years. In 1966 several a maximum rate of thousands per hour were produced.
It is best to look away from the radiant, especially with the moon in view, as Leonid meteors will appear in any part of the sky.
Image generated using Stellarium