Although the link you provided (for your visit to the refugee camps)led me to a post that was written in 2007, the story is very similar. The young men are usually separated by the army and are generally killed. That’s what happened in 2007 and that’s what’s happening now. People and families who come to the camps are separated. Men, women and children are separated and taken to different areas. You can see the pictures yourself from your 'most trusted' website (defence.lk). I can send you more if you need some.

As you can see from the pictures each bus contains either women or men. THEY ARE BEING SEPARATED.

The situation is even worse now. It’s not just the young men who are taken away and killed, many young women have been assaulted, raped and killed as well. The government is eliminating thousands of young people during the screening process.
After 9/11, the line between terrorists and freedom fighters has been erased.

A journalist has to be objective when reporting any news, especially controversial subjects like this. You have just read one side of the story; some anti-LTTE activist and government sites, who haven’t even given a credible chance to the other side
You have to go back and read the history of the conflict. The conflict started as soon as Sri Lanka gained independence. The armed struggle only started following many peace protest with no apparent results.

"There have been credible, independent reports of civilians being forced to remain in the warzone by the LTTE (Liberation Tigers of Tamil Eelam, or Tamil Tigers); then when civilian are slaughtered, this is used as evidence of the Sri Lankan government's brutality (warning – disturbing pictures) ."

How can you say that the reports are ‘credible and independent’ when there are no independent media present in the conflict zone? The government has banned all the independent media and NGOs a long time ago. One of the main demands of Tamil Diaspora overseas is to allow independent media to monitor the events in Sri Lanka. If the government has nothing to hide and not doing anything wrong, why does it not allow independent media to the conflict zone?
Many countries and human rights organizations have said that Sri Lanka is now one of the most dangerous places in the world for human rights defenders - broadly defined to include journalists, aid workers, activists and NGO workers.

"They seem like perfectly genuine people when they tell me that they don't care who wins, they just want the killing to stop. Yet, Nirmala Rajasingam, a Sri Lankan Tamil activist in London, makes a powerful point:
...in all the demonstrations not a single cry, slogan or placard seems to demand that the Tigers should let the civilians go or cease their own assaults on them. The silence of the diaspora community on this issue is deafening... There is no recognition in these demonstrations of the fact that the military objectives of the LTTE are no longer reconcilable with the safety of the trapped civilians. There is a disjunction between propaganda and reality here that reflects the way the logic of Tamil Tiger propaganda has become internalised by much of the diaspora. This does nothing to help Sri Lankan Tamils."

I ask you again. What proof do you have that the tigers are stopping civilians from leaving? Many people who participate in the protests and demonstrations have been effected by this war. I personally know so many who have lost close family members in the last four months and many people whose family are still in the conflict zone. These people whole heartedly support the LTTE. Why do you think that is? Because they know very well, what’s been happening there. Most of the civilians do not want to leave the LTTE controlled areas because of the fear of being tortured, raped and killed by the government forces.

‘I don't think anyone actually thinks of these UN camps as concentration camps, not even those who call the war a campaign of genocide’

Are you kidding me? I am not sure the camps you visited in 2007 had any associations with UN. But the camps that are set up now around the conflict zone has nothing to do with UN. The UN has asked access to these camps many times and been denied. As I said before, the government has banned all the independent media and NGOs from the conflict zone and is even refusing to let them into these camps.
These camps are barbed wired camps where they are kept as prisoners. Aid agencies, foreign diplomats and Journalists are not allowed to see these notorious camps except to the one that is used only for propaganda purposes. Children are separated from their parents and sent to different camps. Yes these do resemble concentration camps.

I beg you to read through all the facts and think objectively about them before writing.

PS: LTTE was formed only thirty years ago after Tamils have been protesting in al forms of non-violence ways without any results. Tamils have been discriminated since Sri Lanka gained independence. The root of the problem has to be dealt with to come up with any sensible solutions.
Having said all this, LTTE consist of human beings as well. They have evolved over thirty years to an organisation that is capable of running a government for Tamils. They have shown that they can do it. Nobody is denying that the LTTE have made mistakes in the past. There are many governments who have made huge mistakes (like Bush government invading Iraq) but that didn’t disqualify them from governing people. Right and wrongs are not black and white as they sound, the actions has to be viewed within the context it happened. You can’t write them off as terrorists just because they made some mistakes in the early stages. They have developed into a mature and disciplined organisation.