I believe TempBot is an account used by the Mag Staff to claim a normal member's thread as news and post it on the frontpage or make a member's scene release official on the Temp. The original poster is usually credited with the news.
TempBot is a bot as its name suggests. Technically it should be possible to make it do all the things you want to do manually, but it is pretty much always used in an automatic way where it handles certain tasks.
What happens when we approve a piece of User Submitted News is that TempBot becomes the topic creator, the topic itself gets moved to the front page and a little text at the bottom of the post gets added ("Contributed by Rydian" for example).