Although legalising or de-criminalising it seems like a good idea, it would probably have some unpleasant effects. The government would probably tax it, making it more expensive than it is, and would probably make it uniform - one strain, one strength etc.

It is harmful. Not in the same way as tobacco, but has been 'proven' to cause respiritory problems and has links to mental health issues.

I don't think they ever will legalise it - if they did, people would sue the government when they got ill.... the way the world is today. Best bet is to go regularly to Amsterdam, where you can smoke what you like, and buy reasonably freely. Or the UK, where although cultivation and supply are illegal, but smoking it (although still theoretically illegal) doesn't prompt any police action.

There are medical MJ trials going on in the UK too. They are working on isolating the THC from weed to give in pill form rather than having people smoke it...