I don't necessarily think preaching is wrong as long as they respect the persons right to decline. For instance, I find nothing wrong with Jehova's Witness's coming to my door and saying, "Have you heard Good News of Christ?" I usually say I'm not interested.
But street preachers really piss me off. Outside my school library there is always a group of preachers screaming about how all us college students are sinners and how he knows all the right answers. When faith is trotted as certitude, it begins to be more than annoying.
JustinC