This is a fast teardown of a COB (Chip On Board) style LED lamp. Unlike the earlier LED lamps that used pre-packaged power LEDs mounted on aluminium core PCBs, these ones mount the bare chips directly on the PCB and then cover them with a protective gel with phosphor in it if required. This improves thermal conduction to the main heatsink and also cuts down the cost for the manufacturers dramatically. This technique allows them to create custom shaped power-LED panels and wire them in series/parallel arrays as required. This partticular lamp was interesting in that it used a traditionally shaped Luxeon Star type base. Probably to facilitate use of an existing heatsink style pre-drilled for that package.
The power supply is sleeved in nice thick heatshrink in this light which is nice. I wouldn't rely on these little supplies being properly isolated from the mains due to the way their little transformers are wound with primary and secondary windings in close contact. Likewise the LED PCB is closely coupled to the aluminium heatsink with screws that overlap the PCB tracks. So I'd always treat the exposed metal of LED lamps as being potentially live as a precaution.
Very smart looking lamp with a nice wide beam of useful light. In open air the metal does get hot to the touch. I sometimes wonder if the manufacturers are compromising LED life with undersized heatsinks.