Any thoughtful person who knows history and religion would be anti-Islam. Along with Communism, Naziism, and the Black Death, Islam has been responsible for more death and destruction on the face of the planet than just about anything else since the last asteroid impact. Islam was started by predators. It has spread by predation. It has lived off the decaying corpses of the civilizations it has destroyed. It is a vast, ancient sea of corruption, oppression, fanaticism, and ignorance lapping up against the shores of the present, kept alive by the fortuitous accident of living above huge reserves of petroleum.
"...Do you think there's any truth to that imam's claim who recently said that thousands of Muslim every day are converting to Christianity?"
you may find this site of interest:
http://muslim-quotes.netfirms.com/islamgrows.html
example:
How many Muslims have been lost to Islam in the last fifty years here ? Tens of thousands have been lost. The only reason Islam is still growing here, by large, is because of a steady stream of immigration. But when that dries up, the assimilation will dwindle our community down to nothing. It's like we have a bucket with a hole in the bottom. We keep pouring new immigrants in, but so many are leaking out are lost forever.