If you're posting your photos online it would be beneficial to read the Terms & Conditions of websites you are currently using or intend to use. The Terms might state that when you sign up to use the site, you're automatically agreeing to their Terms.
Terms seem to often include something to the effect that you own your photos - but..... the rest of what's stated may include allowing the site unlimited, uncompensated usage, and might include usage by third parties. You'd need to read what you're allowing because not only does stealing photos online seem to be rampant but you might be allowing the site to use your photos without your permission or knowledge or any compensation.
If reblogging or reposting is allowed and you've agreed to that, it doesn't seem like your photos would still be under your control. I know a couple of photographers in my area who post select photos only online to display and then provide links to their own websites. Using a site where you can post and sell photos might be an option (as Overread mentioned as #5 in his post).
To do professional work in photography I'd think too about what you post on message boards; you seemed to be doing a little name dropping of sorts and that might be more than what a client would want to have posted online about work you've done for them. For example a client may want the photos to go public on a specific time frame so you wouldn't want to be sharing that info. or the photos online prior to an intended release date.
ASMP has information that could be helpful in going into business as a photographer. They also have had info. on their site recently regarding the latest changes to TOS on Facebook that were supposed to go into effect this week.