guys settle down. no need to fight and instigate trouble.
i think what toasted meant was that it will not be an exact replacement without rooting. yes you can download an app from the market but it will just be layered over the original lock screen instead of replacing it. from what i have heard that app is not exactly the most reliable either. sometimes it doesn't work and sometimes it will make you unlock 2 times. maybe they fixed the bugs but thats what i remember from an earlier release as well as hearing from other people.
if you want an actual replacement lock screen then you are going to have to root. if layering it over the original works good enough then rooting might not be necessary.