I hope Sony actually goes through with this. I currently use an ipad mini & notesplus with a jot pro - it's a good setup and works well, but I still find myself reaching for legal pads half the time.
I currently use a Surface Pro with OneNote (full version, skip the W8 app store version), and it's fantastic. I have actually stopped using the hardcover sketchbooks I normally carry around, and the Surface takes up space than those books.
StylusLabs Write is a pretty great app too, and it's available for most major platforms.
You might want to consider one of the smaller tablets that have a real Wacom digitizer, i.e. Samsung's Note / Pro series or Asus' new W8 8" tablet. I don't know about how good the Dell Venue Pro 8 is, since its stylus isn't a Wacom.