Drives are very cheap. Doing backup of the drives continues to be a stone in the shoe, though
That's what more drives are for.
You're missing the point.
That is why raid 1 was invented, two identical drives that automatically backs itself up to the other.
OK, two misconceptions here:
First, RAID-1 is not "two identical drives that automatically backs itself up to the other". RAID-1 is writing data identically to two drives all the time, producing a "mirrored set" (when reading you don't have to read from both drives). See http://en.wikipedia.org/wiki/RAID#RAID_1
Secondly, RAID is used to protect you against accidental drive crashes (except for RAID-0, where there is no redundancy) and to get very large drive volumes, not to protect against deletions because deletions are recorded on all disks at the same time.
Backup ... is backup! Backup ensures that when you accidentally deleted at file, you can find it and restore it. So using RAID and backup are really orthogonal issues.
The reason that backup is 'expensive' is that it takes a lot of time (and performance out of your system) to rummage through your terabytes storage, and whirling off the changes to your backup platform. It's so expensive in terms of performance and time, that people just don't do full backups all the time, but only during weekends to be able to complete the backup before people come back to work Monday morning.
But yes, this is decidedly outside the 7D2 discussion.
I gave up waiting for the 7D2 last year and went for the 5D3 (I'm still in love with it). But an 7D2 like RLPhoto predicted would be very interesting indeed!
I'm crossing my fingers that Canon have been able to work on the IQ - I was always disappointed with the 'mushy' pictures from my 50D, and my friends' 7D was no better.