Since the thieves probably vacuumed Tapastic's servers, it means that all of our stuff - whether we create manga or not was at risk of copyright infringement and abuse. They could have one manga site and another for American comics and so on. We probably didn't see all of their operations. It's the tip of the iceberg, I would say.
So Tapastic should probably address this with the community and tell what they'll do to prevent rogues from vacuuming their server's contents in the future. If you host your comics portals, ask them too and make sure each of them is aware of the problem.
If you use something like Tumblr, I'd be very careful as the architecture of such a system makes it easy to develop plug ins.
If you host on your own site, unless you are well known you will have limited security through obscurity - because few know about you, few will steal from you. This is not a great protection, but you shouldn't worry as much.
Disclosure I research information security and usability at the university which is why I'm so gung ho abut this issue. Its too close for comfort!
