I really don't understand this. I have done all the flashpoints so far with my guild, so I am never looking for a group for these instances, however, I have been whispered several times and it has never bothered me. The people I have gotten whipsers from have been friendly, aren't begging, and usually even tell me to have a nice day or something after they have asked. Why in the hell would I blacklist them? They are getting a group formed while others are here complaining.
Yes, I would like to see a channel added or some kind of a tool added (NOT LFD but simply a LFG too lthat helps put groups together). However, right now, most people are still leveling and only doing flashopints occasionally. I am at 38 now on my main, 23 on my alt. There are very very few people around me at 38, while there is still usually a queue to get on to the server. That tells me that most people are still lower in level (or all on the empre side).
I am guessing a lot of the difficulty people are having relates to level, and Republic vs Empire..