Hmmmmm I wonder what's going on behind the scenes here.
Fox see's fans getting very excited about another "Alien" movie. Then there's a tug of war between Ridley wanting to do Prometheus 2 and Blomkamp wanting to do Alien 5. We know Blomkamp's concepts are stepping on Ridley's toes a bit.
Ridley being the workaholic he is and wanting to get his project on the go suggests; "hey I can just Alien up Prometheus 2 if you guys want, two birds one stone". Blomkamp thinks "shiiiiiiiiiiiit".
In the end though, does it really make sense for Ridley to be working on a series of films leading up to the original and Blomkamp making a different Alien movie in the distant future of that universe. Honestly, how do they market those movies unless of course they were to somehow link up?
UPDATE
Well I just read the Empire piece. I sure as shit spoke too soon.