I just checked them out and saw some hot covers. I checked an author's blog on them as well and she seems happy.
I too want to know what 'established' mean.
Seems open to interpretation.
"Established" for an epublisher means their authors can expect decent sales--first-month sales in at least the low triple digits. "Established" means you've actually heard of them and so have readers and other writers. "Established" means you've heard of their writers.
It's very easy for any publisher to have "happy" authors--look at how many people are pleased with PA. I'm not saying Forbidden is a scam, just that finding an author who won't publicly say she's not happy--most epubbed writers don't say such things publicly--means nothing.
Forbidden has no sales data at EREC. I don't know any of their writers.
If you're looking to submit to an ehouse, go for the big established names first: Ellora's Cave, Samhain, Liquid Silver, Loose-Id. The ones with an established customer base--ereaders tend to be loyal, and it's extremely hard for new epublisher to attract new readers, especially given how glutted the ebook market already is.
JMO, but there's no reason to submit to Forbidden when there are much bigger, better houses to submit to.