A lot of people view the life that Jesus lived and Socialism as very similar. They feel that both Jesus and Socialism want a redistribution of wealth to benefit the poor. Socialism kind of takes the role of Robin Hood in taking from the rich and giving it to the poor. That sounds awesome in story books, but I know that even if I wanted to help people I would still get pissed if someone just took my stuff and gave it away, leaving me and my desire out of the equation.
I think the main difference, and a very important one, between what Jesus is trying to usher in and the goal of socialism is that while socialism forces the redistribution of wealth, Jesus does not. Jesus wants our heart to change so that we realize that what we "own" is not our own. It is His and he has given us temporary possession of it. We have no claim over it. Therefore we should give freely. We should desire to love and help the poor. To proclaim to them the gospel by living it and helping them meet the needs they have by using the abundance of things that Jesus has given into our hands. Love is the motivating factor behind the life of Jesus and how He calls his followers to live.