After an initial run of a system of 200+ lasers pointed at a diamond capsule used 2 kJ of energy to release 3.15 kJ (which might not seem like much, but getting a fusion reaction to have a net energy gain is a monumental achievement), the National Ignition Facility has managed the trick two more times. They say it's now primarily a matter of improving the technology and scaling the system up for useful amounts of power generation while reducing costs.
I'll reserve my excitement for when we actually get a fusion power plant online and pumping energy into my microwave oven, but this is at least a promising development.