thejadedmonkey
macrumors G3
I couldn't imagine needing more than 16 gigs of Ram, but I might be shortsighted. As far as upgrading the HDD, it's actually SSD and from what I understand it is upgradable. Now, Apple may not offer a 2TB SSD right now, but in the 3 years that you mention they probably will, and I'm guessing you can put it in your retina then
You'd have a hard time getting Apple to upgrade the HDD on a classic MacBook pro, let alone a laptop where it's specifically "non-upgradable".
As far as needing 16 or 32 gigs of RAM, right now if I developed on my mac, I would use 3 for Windows, 3 for OS X, 2 for Windows Phone emulators, and that's 8gb for my normal "light" usage. Ideally I'd want closer to 10gigs, and that's just what I use now. Who knows what I'll be doing 3 years from now.
The MacBook pro retina just isn't ideal for a hardcore user, but it's priced to target the hardcore user. It's a strange marketing conundrum.