I've had that same experience with my blog, meeting people who only knew me from this blog, but carrying on a conversation that seemed like they were "inside my head." This quote ties personal branding directly to an ePortfolio for employability:
[Scott] Karp says he built his brand at Publishing 2.0, using it as a soapbox of ideas and a forum to discuss them through comments."My blog became resume, business card, references, network all in one," Karp told me. "I would go to conferences, meet people, and find they already 'knew' me through my blog -- an odd but useful form of micro-celebrity."
"When you're considering switching jobs, even a personal website with a small portfolio of sample work can be invaluable," [Matt] Cutts [of Google] said. "People will search for you online, so it's important to take part in that conversation, and having your own website can be a great way to put your best foot forward."
"Grab a domain name and work on burnishing your personal reputation online. It's definitely not the case that everyone needs a blog, but having one place that acts as a face to the world can really help. There's room for a resume/CV, but also for some writing samples that show off your abilities." -- Matt Cutts, Google (from his Letter to a young journalist post)
Isn't that a portfolio? I also love this quote:
Even more illuminating are the comments that appeared from other readers of the article:
...And in this era, you need to be very careful, as search engines can log all sorts of things. Remember: Whatever happens in Vegas...stays on Google." -- Scott Monty, Ford Motor Co.
I find the whole idea of personal branding both a necessity and an opportunity to find ones true voice.
Remember MONEY magazine said in there 12/07 issue - "You're only as good as Google says you are"
Personal branding, to my opinion, is a tool to tell people who you are and what is your unique contribution to the business. It validates and manifests the inner knowledge of your being and empowers you to act freely to your full potential.