Okay, I've seen this one thrice too many on Facebook. People writing "von voyage" to, well, wish their friends a happy trip. The intention is appreciated BUT, as far as I know and as verified by Google (including dictionary dotcom), it should be "bon voyage" not "von voyage."
But because Facebook (and other social media websites) seem to thrive on making trends out of the usual and ordinary, I just don't know if using "von voyage" is just one of those trends that people trying to be "cute" (heheh) are using nowadays.
Anyway, I'm sticking to using "bon voyage" (in and out of the Internet) because I'm already cute (heheh).