My personal opinion is that it is a lot less harmful and self-destructive than other recreational drugs, including alcohol. I agree it should be decriminalized, because our courts and jails are overflowing with small-time users who are otherwise law-abiding citizens.

I strongly disagree with the Times article that you quote; it can only be understood in the context of the current political row in Britain. The Times does not really make any case against marijuana but rather says studies show it might be harmful and claims there is no benefit to compensate for possible harm. It also repeats the old saw about it staying in the body longer and worries about stronger new (more than 10 years old actually) forms being more dangerous but neither of these things proves harm in themselves.

But to return to the article and its context, the current British government has just fired its leading expert and adviser on drugs, Professor David Nutt, because it didn't like his advice. He and the others on the British expert panel, some of whom have resigned in protest, had the gall to conclude that while Cannabis may be somewhat harmful, it was a heck of a lot less harmful than tobacco or alcohol. In fact, they did a thorough survey of illegal and legal drugs and published a paper listing them in order of harmfulness. They apparently advised the government to bring its classification system into line with the scientific evidence. The order on the list was not politically correct and the Professor was fired.

There is a lot of interesting discussion of all this in the British news, I was considering forming questions about it myself.
http://www.guardian.co.uk/science/2009/nov/02/david-nutt-dangerous-drug-list
is the Professor's list. Elsewhere he suggests that the drugs above alcohol should be class A, and the ones below tobacco class C.
This article in the Guardian draws parallels with Galileo and the Popes.
http://www.guardian.co.uk/politics/2009/nov/03/scientists-politicians-disagree

I agree fully with David Nutt. Stuff that can and does frequently kill people should be considered more harmful than stuff which doesn't. And stuff that has been proven harmful should be considered more harmful than stuff that might be harmful but years and years of research has been unable to convincingly demonstrate.

"Rather than arguing whether cannabis should be a Class B or C drug, politicians would be better to support a big educational campaign on the properties and constituents of different types of cannabis and the risks associated with heavy use."
http://www.timesonline.co.uk/tol/comment/columnists/guest_contributors/article6900001.ece#cid=OTC-RSS&attr=2270657

I think this about sums it up quite nicely. Few would argue that pot is totally without risk. People just need to be aware that there are risks particularly with heavy use.

As mentioned in the quote above, I am not sure this has much of an impact on if it should be legal. It simply means that people should be aware there is no risk free drug.

i confess I did not read that particular study, but no I do not believe most studies on anything medical. I think most of those studies have been paid for by companies and there fore the ones who do the studies tend to state what ever the company paying them wants to be said.

I dislike studies, which can be seriously flawed, and tend to rely on other people's first hand experience to judge things.

For years we have seen those people who smoke pot around us, sometimes (depends on how much they smoke) they are healthier then others. I know they say pot is good for the side effects from radiation with cancer treatments. Too much pot is bad if if makes you crazy and do stupid things, but if it helps you calm a tummy down after radiation or eases arthritis pain better then harmful side effects we get from medications I am all for it.