Why can't I download the Minecraft PC version?

So today I was planning on buying Minecraft for my new Windows laptop off of their main site www.Minecraft.net. I signed in my Mojang profile and started the process of purchasing. I filled out my ccard info. And hit purchase. It loads not even 2 seconds and says "can't complete this process. Comeback later and try again". So I wait… And wait. Then try again. SAME THING! I mean I have the game for my 360 already but I really wanna try the PC version… Help?!

It 'may' well be the site is down for maintenance or updating.
(It does HAVE to be done at some stage!)

I would add, most sites do this on the weekend - especially a Sunday.