I also don't understand why some (not all) get so opinionated or irked when someone posts something on the rumour mill.
The clues in the name, its a rumour and supposed to just be a bit of fun. Either believe what the poster says, or don't. It's not life and death. I like to read the rumours but until a new signing has signed on the dotted line, really it matters not one jot whether I had heard the rumour a week before or who had provided it.
I also don't understand why there is usually a clammer for the poster to provide the 'source'. If the original poster wants to provide it then fine, but if not just take their post with a pinch of salt until things are officially announced.
If they didn't post their 'in the know' stuff, or even their fantasist stuff, it would be very quiet on here. Keep the unsubstantiated rumours coming I say. Up to the reader what they believe.