please advice about soc.bookmarking with 1 account only

for SEO:
Hi, is it terrible to use for easiness 1 account to do social bookmarking for 15+ websites? or is it more or less no huge difference?

for Security?
All my sites don't have privacy. I don't wanna pay 10 per site for this.

Other?

Thanks for your advice.

And is it maybe dangerous to have "all eggs in 1 basket"? I heard sometimes accounts get closed and all bookmarks deleted. So if I for example digg 1000 articles over months then it would be rather sad if they might ban the account?

Also can't other "money makers" follow your "footprint" and discover all your sites?

Thank you for your advice.

seems you already know your answers lol