this is basically just a misconception. A cmbp is just as likely to run into problems as a rmbp, but the rmbp has had some issues with its screen. Then again, that's basically it. The difference is that the rmbp is a new machine. This makes people create new topics about their issues since old ones with a solution doesn't exist yet, hence, the flow of problem-topics you see with the retina.
A lot of people try to justify their purchase of either a rmbp or a cmbp these days (or rather, since the release of the rmbp), and i have to say that i personally see no reason whatsoever to buy a cmbp anymore, but they are still both great machines.
I am however a bit fed up with people claiming that the cmbp is a better buy. Unless you use dvd's a lot and you don't want a superdrive, or you really need upgradeability, i see no reason to buy the cmbp over the rmbp.
But as others said, you buy what you need.
And to the op, i can't think of a task i can do with a imac that i can't with a rmbp. Spec-wise they are very similar (though the imac can be specced higher, of course), but the rmbp has the portability, the screen, the power. All in one awesome package. But the imac is a great deal for the money if you don't need to carry your work around with you (or around the house).
both feel like they need justifying their purchase, as if that will make the future of their product more/less certain.
