I think the number of subscribers has increased a lot lately, i'd say somewhere around 750k, and rising.
Once new content rolls out things will get even better.
I actually think it's rising again as well. I've seen quite a few "Hurray, I just got my sub" yells this week.
F2P gives a very good try-before-you-buy, and that's the whole idea behind it in the first place. Get people to either subscribe, or have them spend a load of money to unlock their game to near-subscrition capabilities. F2P isn't to actually give you all benefits possible without paying. It's made with a lot of inconveniences (and that's really all they are!) to make you seriously consider subscribing, on the premise that one hour or more of fun every day for a whole month is worth the value of one round of beer in the pub with at most 4 friends, which are downed within 30 minutes. (and that's small glasses of cheap beer you're putting in then.)