I'm anal about alot of stuff. I read on sticky somewhere that I don't want an "advance" board to start off for x reasons. I just don't want to be the guy that drops $300 on a board just to find out that I bought the wrong board. That's all. A little DD on my part.
I'll tell you my experience and maybe that'll help you. I went a couple of times and rode rentals and knew I was going to stick with it. I picked up a used board on CL for $75. It was a park noodle. It was great to learn on! Super soft and really helped me to learn to turn. However, I was struggling to deal with speed and especially turning at speed. My buddy and I swapped boards for a run and he said, "Dude! It's not you, it's the board! That thing is SCARY at speed!" Being a park noodle, when you got it up to speed, there was a ton of chatter and it just did not feel comfortable committing hard to an edge when turning at high speeds. Basically, I'd come as far as I could in the freeride area while riding a park noodle. I bit the bullet and bought an '09 NS Heritage. Huge difference! I was able to progress and get a lot better. But, I still have my old noodle and with it being my first board, I'll probably never let it go. I still take it out occasionally, because while you can't bomb with it, it's still a super fun little board to tool around on.
In short, to begin with, a soft park board is easiest to learn to turn and link turns, but as soon as you feel comfortable linking turns, you'll be a lot better off with a stiffer all-mountain or freeride board. The good thing about picking up a used park board to start with is that when/if you want to start jibbing, you've already got a suitable board in your quiver!