I'm jumping on the MJ/Volls bandwagon. I don't see the physical effects of marijuana being worse than those of alcohol. I will say that I prefer the company of stoners to that of drunks, perhaps because I spent many years as a stoner myself. Drunks are more obnoxious by my estimation.

As for pot being a "gateway" drug, I think that classification has been applied not because of the inherent physical/mental effects of marijuana itself. It seems to me that the likelihood of coming into contact with other illegal substances increases when interacting with marijuana dealers (because nobody "just sells pot"). If marijuana were no longer confined to illegal channels of distribution, it would no longer be tied up in markets that promote the use of harder substances.

That's just my opinion, though.