Dx9. Actually the game runs perfectly on my laptop (ATI card), the tails looks great and everything works perfect, but in my other PC (Nvidia 9800GT) it looks like the tail is "smaller", also it doesn't show up while running backwards.
I was trying to record the bug with FRAPS, and surprisingly the tail looked larger. More similar to what it used to be on the demo but yet not the same. In the second I turn off fraps it looks smaller again...