What a great question! You are on the right track. First, lets define Avatar as "An icon or figure representing a particular person." In business application, an avatar is a representation of your ideal client/customer. A business may have multiple avatars representing several target demographics...
First of all, you need to get really clear on who your actual customer is, and where they are. Are you actually selling direct to Gen Y (ie, internet, retail stores, etc) or is Gen Y your end user (ie, you're really selling to distributors or directly to corporations, site managers, HR profession...
If there are any general similarities or common ground between the two target markets you can accomplish this goal with a single blog using target market-specific keywords and category names. I have a client who is in the home improvement industry, installing replacement roofs, siding, windows, d...