Micro-inverter or panel electronics.
It's like the Microsoft-Apple debate insolarpanels.
Micro-inverter companies like Enphase Energy say they can increase the power produced by solar panels by attaching an individual inverter to each one. With an individual inverter, panels exposed to bright sun won't be dragged down to the level of those in the shade or coated with dirt. Micro-inverters can also be integrated into panels to produce the all-in-one solar panel.
By contrast, Tigo Energy and National Semiconductor argue that it's better to use a single, central inverter and maximize power output through electronics inserted on each panel. Inverters have a higher failure rate than panels, these companies claim (micro-inverter companies vociferously dispute this). Perhaps more persuasively, these companies argue that a central inverter strategy is simpler. Much of the energy harvesting and control takes place through software.
The market will ultimately decide which one works best for which applications. In the meantime, check out the video with Tigo CEO Sam Arditi taken at Intersolar.