Striker fired compact 9mm seems to be the popular desire/speculation.
Some want single stack. I would prefer a double stack compact 9mm my self. Give me a 3 1/2 inch barrel and a slim slide. I'll deal with a think grip. I would love one that the mags interchanges with my P89. Like the Glock 26 can accept a Glock 17 mag.
I heard about the SR9 from a pretty good source and it is supposedly in production. The first release will have a longer barrel, but the next release will be shorter. It is supposed to be a slim piece, but I don't know whether single or double stack. I think single stack. I have been looking at all of the compact and mouse size 9mm and I still have not found what I want. I can only hope for an answer from Ruger. Most of the really small 9mm pocket pistols are either unreliable or too expensive, so Ruger could clean up with a truly small sub compact 9 about the size of the Bersa T380CC which I own.
I am saving my pennies for my next purchase, but I am looking at PC9, BH convertible .357/9mm and I am considering a mini 14. I have also lusted for a mini 30, but $$$$ so we will see. I am going to wait to see what Ruger comes out with before I buy anything else. I have bought a shotgun and 3 pistols this year so I have been out of the market for awhile, but my toy fund is growing and I am waiting.