The first few rounds were met with frustration from transgender advocates and anti-bullying advocates because it only covered "sexual orientation" as its LGBT protection. Therefore, some transgender persons felt vulnerable because employers would likely claim that transgender persons could be discriminated against under the notion that it's not really their "orientation" or their "gender" that is being scrutinized.
Some were also dissatisfied because a person who is only perceived to be gay or straight by their peers should be protected equally as well. You know... some people might get fired just because of their mannerisms.
Barney Frank and other Democrats finally gave in and said 'no more half measures' so now the new ENDA bill specifically protects transgender people and "perceived sexual orientation" as well... In a nutshell, this means that if an employee SEEMS like a gay person to you, that's not an excuse to fire them either.
This is not the first law to protect people on the basis of their "perceived" sexual orientation - the Mathew Shepard Act features the same language.
Now, the biggest problem that conservatives say that they have with measures like ENDA is their fear that Religion will be affected adversely and their morals will be compromised. That's gone now too - because the new bill exempts religious organizations from having to hire LGBT persons if they don't want to.
But this time, the big hurdle that ENDA must cross is Rep. John Paul Kline (R-MN) who said as part of his campaign that "Job creation is his #1 priority".
Kline is now painting the new additions as "vague language" which are meant to confuse the matter. He pretends not to know what "perceived sexual orientation" means and claims that exempting all religious organizations from this law is still just too risky for Christians... because, well, you know... it's totally against everyone's religion to have to work with people they don't like.
Here's an excerpt from the Windy City Times:
Kline said back then that ENDA "creates an entirely new protected class that is vaguely defined and often subjective." Specifically, he objected to the language of the bill prohibiting discrimination based on "perceived sexual orientation."
"Attempting to legislate individual perceptions is truly uncharted territory," said Kline, "and it does not take a legal scholar to recognize that such vaguely defined protections will lead to an explosion in litigation and inconsistent judicial decisions."
Kline also said he thought legislators should consider the "consequences" ENDA might have on "religious and family-based organizations."