The companies developing technology that uses existing electrical wiring in a house to build a network seem doomed for failure: When Wi-Fi is cheap, easy and better, why bother using one of these HomePlug solutions? With Wi-Fi you can hang out anywhere and get online, instead of only next to an outlet. Seems like a no-brainer.
Before Wireless Distribution System (WDS) became widespread this year, a HomePlug bridge might have made sense to avoid running wire between access points. That's now moot.