Malicious subscribers?

I launched a new site a few days ago. It has at this point very little content and very low traffic. But, since yesterday a dozen new subscribers have registered, and they are coming now at the rate of about one per hour. Many have similar email accounts. My other sites with low traffic – but not this low – rarely get subscribers. Should I be happy that I’m getting subscribers or concerned that something bad could be coming? Note: In spite of it’s name, the site is SFW. It is a celebration of successful women, not what you might think.

The page I need help with: [log in to see the link]