1. Numbers. Although it has become politically incorrect in some circles to say so, numbers are key. We look not only at the number of readers reached through an individual's blog, but also her Twitter stream and Facebook page. Clearly, if a blog is huge but its focus is irrelevant to your brand -- i.e., if you're pitching a toy to a mom blogger who only posts about politics -- size doesn't matter. The same is true with niche products: If you have a product for a disabled child, it's more effective to target a blog popular among parents of disabled children than one reaching a general audience, regardless of how impressive those general audience figures might look.
2. Engagement. Are readers commenting on what a blogger has said? If so, it means they are paying attention and care about the topics the blogger has chosen. Are other bloggers linking back to her on a regular basis?
3. Frequency. Posting daily or at least a few times a week offers more value than less-frequent updates. The more often a blogger posts fresh content, the more often readers will come back for additional information.
4. Quality. Bloggers who clearly put effort into their posts -- who aren't just copying and pasting parts of press releases, but spending time experiencing a product or service and providing their honest personal opinion -- will be more credible than those who are taking the lazy way out. Readers want to know what the blogger thinks of a product -- not simply what a company wants them to say about it.
5. Visibility. Are these moms a major part of the media scene? There are numerous blogger/social media conferences around the country: Do these moms speak on conference panels or at least regularly attend the events? When bloggers are positioned as experts or make an effort to be an active part of the community in real life, more readers will be drawn to them and rely on what they have to say.
There are other factors to consider, of course, but these are important first steps when identifying mom bloggers who can most persuasively present your brand to other moms.