Lumens is the light output of a lamp and candela or millicandela is a measure of apparent brightness.
A 100 watt incandescent bulb produces about 1500 to 1700 lumens. LED lamps are available with ES (Edison Screw) or BC (Bayonet Cap, push and twist) bases. At present these are generally available in 60 watt versions. 100 watt equivalents are available but not as easy to source at the moment. A 60 watt equivalent LED lamp uses about 10 watts of electricity.
Individual 5mm standard LEDs (the size used as an indicator LED) are commonly available with a brightness of 15,000 milli-candela or 15 candela over a beam angle of 15 degrees. This equates to about 2 lumens.
Philips Lumileds manufacture a device less than 1/2 inch square made up of hundreds of LEDs which has an output of 1150 lumens at 10 watts.
Citizen have produced a device with an output over 17,000 lumens at 183 watts which is brighter than a large flood light.
Cree produce lots of high brightness LEDS for use in their torches. Torches can produce the equivalent light output of a 60 watt incandescent bulb.