I have replaced some halogen bulbs with LEDs in the kitchen and they appear to be glowing gently when turned off. Any idea why?

Are they controlled by one switch or two?

Residual charge and capacitor effect stuff.

http://www.diynot.com/diy/threads/led-downlights-glow-slightly-with-power-off.164167/#post-1110158

You get similar with CFL energy saver bulbs with dull flashes in the dark every now and again. I see that from mine in the bedroom when off.

Only one switch. Not down lighters but set if four directional lights. Does not flicker but stays on just very dim. Interesting about residual charge was concerned about earth leakage if this is a thing.

I had this with some 12v lights with a pishy transformer.

Solution for me was to rip out the 12v stuff and fit 240v kit