Right. Statistically, it's close, I agree. The following points are why i think Ronaldo is better right now though. However the following statements are all purely opinionated and therefore shouldn't be taken as facts, just a personal opinion.
IMHO, Ronaldo has been better simply because he's near-singlehandedly dragged Madrid to their most successful year in modern history. I believe that it doesn't matter if you score a lot of goals, if it means your team doesn't have success. Mainly because players are there to serve their team before going for personal records, and the best way to serve a team is to win them matches and trophies. Ronaldo has done so, along with his individual brilliance.
Now you may hit me back with Messi's World Cup campaign. And you're right, Messi did get them to the final. However a one month competition, no matter how great, is still a one month competition. One month out of twelve. You do the math. Messi was great in the World Cup, but he has to constantly show that, and for me, he just hasn't done that this year. Whenever I've watched him, he hasn't had that 'sparkle'. Of course, this is all still personal opinion/bias.
And finally, stats. While I don't like people basing their opinion on a player based solely on stats, I believe that dtats still have to be taken into consideration when comparing two players. Statistically, Ronaldo has had a better year and season so far, and in less games. Of course, you might put this down to Madrid having a superior squad to Barca, but IMO, the difference isn't as huge as some are making out them to be. I believe that the Messi of 2012 would have hit Ronaldo-heights or even higher even in this current Barca team; his standards have dropped, that's undeniable.
So there, those are my arguements for why think Ronaldo is currently better than Messi. Is that well-structured enough for you?