Much to-do has been made of late in the SBC (folks I appreciate and love) about the so-called "sinner's prayer". This goes to the very heart of the gospel, conversion, and evangelism.
One major problem in contemporary Christianity is false conversions. People have an experience, maybe repeat some prayer, and then they're given assurance of salvation. This ought not to be! Assurance must come, not from fellow man, but from the Holy Spirit, and as the fruit of an obedient life is seen as increasing (though never perfect).
Listen to watch Paul Washer had to say on this subject -- I think he is exactly right: