First Attempt At Screencasting

I finally broke down, taking about two hours to start constructing some materials and created my first screen cast. Through this i was able to play with camtasia, looking at editting clips, which was a lot easier than i originally thought. I felt that my first attempt went very well, but was not up to par. I tried more and more to practice this skill, and things are starting to get better.

Now that things are starting to get easier, i have the next roadblock, what should i be using my screencasts for. Should i teach with them, let them be review, or just be a resource? What are you currently using screen casts for in your classroom, whether it is math, science, history, or gym? And how are yo u uploading them, are you simply posting on youtube, or someplace else?

I am new to this and any help is appreciated and i am sure that this woiuld be helpful to others as well.