Damn it, man! I wasn't ready for that at all. I wish they'd released a trailer for the teaser for the trailer for the teaser-trailer you just posted a few weeks ago so I could have been better-prepared.
I don't like the term "remake" when the first movie isn't some original idea either. They're both adapting a pre-existing story. And from what I understand there's quite a few differences between the two movies. As for why they went with "Total Recall," money is a pretty safe bet.
From the trailer there is no mention of asses and attempting to get them to mars. It will be nigh impossible to supplant spot reserved in my heart for the Arnold version, I wish it luck. Collin Farrel is already kind of a minus.