How about Vapor? Go viral and turn your Vapor into Steem. It's easy to pronounce, 2 syllables (2 or less seems best IMO), and plays well into the "steam" metaphor. Also it starts with a "V", so a corollary to Videos is easy to make.
Only downside is you'd need to get creative with the domain name. You could probably buy vapor.tv but vapor.io is in use by a "Cloud" company.