It appears that there is a good chance that Marwan Barghouti will be released, either as part of a deal to get Gilad Shalit back or as a "goodwill gesture." The fact that Olmert the habitual liar is denying it only lends it more credence.
Barghouti is an interesting person. From a purely objective viewpoint, he may be the best-qualified leader for Palestinian Arabs. He was a leader of the first Intifada which was home-grown (not run by proxy by Arafat from Tunisia) and a leader of the "young guard" of Fatah. He opposed Yasir Arafat's corruption, although Arafat the master politician managed to co-opt the intifada and used it to re-assert his leadership of the native Palestinian Arabs, marginalizing the first intifada's leaders.
Barghouti remained opposed to Arafat through the rest of the syphilitic terrorist's life, and considered a run for PA president after Arafat died, finally demurring in the name of Fatah unity.
Since then he has fully split from Fatah, starting his own political party from prison named al-Mustaqbal ("The Future") with other members of the "young guard." Unlike Fatah's entrenched, corrupt and senile leadership, the "young guard" seems to truly care about Palestinian Arabs.
Some advocate his release to strengthen Fatah against Hamas, even though he is no longer a Fatah member. He is respected by Hamas as well and is rumored to have been instrumental in the formation of the short-lived Fatah/Hamas unity government. He seems to a accept Israel's existence.
The only problem is that he is a terrorist. He has supported the murder of civilians who live beyond the Green Line and he was convicted of murdering five; he was the head of Tanzim during the beginning of the second intifada and Tanzim murdered many more.
(Incidentally, in his trial he was only convicted of murder of five civilians [thanks for the correction from Soccer Dad - EoZ] plus one attempted murder; and he was acquitted of other murder charges. But as head of Tanzim he certainly bears some level of responsibility for the outbreak and escalation of the second intifada.)
Here we have the Palestinian Arab story in a nutshell. Historically, they have been led by incompetent, corrupt and selfish leaders. Yet their most competent and least corrupt leaders are still unrepentant terrorists.
And it cannot be any other way. Since the Palestinian Arab psyche is so heavily invested in making murderers into heroes, it is impossible to imagine in this generation that an effective leader could emerge who is not a terrorist. Simply put, if you haven't spent time in Israeli jails for murder, you have no street cred.
The world has implicitly accepted this for decades. Rather than insisting on changing Palestinian Arab society from the ground up to be tolerant, liberal and moral, the world accepts as an unchangeable fact that Palestinian Arabs will remain enthralled with child murderers and terrorists, and the hope is that their leaders will not be quite as bad as others. Compared to Hamas or Al Qaeda, Barghouti the multiple murderer and terrorist looks positively saint-like, and he has more than his share of fans among the left worldwide.
This is today's "realpolitick" - better a murderer than an extremist murderer. The idea that a non-murderer, someone who truly wants peace and is willing to work for it, could be a popular leader of Palestinian Arabs is so absurd as to be considered fantasy.
This logic might make sense to the people who are not the stated targets of the terrorists, but to most Israelis the distinction is not too relevant.