Huh, found this thread with a Google search. And, apparently it's still active.
I'm currently in transition. I've owned a 15" Macbook Pro (non-retina) for the last 1.5 years now. I love the thing. The most demanding of my tasks is Logic, where all the plugins I use can quickly push a machine with a lesser processor beyond its limits. The i7 in this machine handles it just fine.
So, to say those quad core i7s are overkill: Usually, yes. But, there are definitely cases where they make all the difference. Even with an i5 in the 15" Pro (back when that was offered), the performance suffers quite dramatically for this use case.
That said, I'm trying something new now. It's a two-pronged approach.
I just picked up a refurbished 27" iMac, with the 3.4ghz i7, 8gb of RAM, 1TB Fusion Drive, and the 2gb Nvidia Graphics. In terms of raw performance, this isn't a HUGE step up from my 15" Pro. But, in terms of some general... comforts, it's a lot better. Specifically, even under a decent load, this thing is SILENT. For me, this is one of the biggest negatives associated with laptops in general. If I'm mixing in Logic on my 15" Pro, the fans are always going full speed. If I'm editing photos in Aperture, the fans are going full speed. On the iMac, unless I'm playing a game... it's silent. Some day, when I work up the balls to start recording vocals, this will be essential. And, frankly, sitting in front of a computer with a fan that's screaming at you for hours on end... it's stressful! Of course, that's not to mention the insane screen real estate the 27" screen affords. I've never really minded working on 13" or 15" laptop screens, but I can't deny the benefits of having this much space to work with.
So, prong two? I realized quite quickly after picking up the iMac that my Macbook Pro is completely overkill as a laptop now. While having that much processing power on the go is nice, it's just unnecessary now. I use my laptop for work, more casual computing (ie. not at my desk), and obviously whenever I don't have access to my iMac. I bring it to the office everyday and hook up to a 27" Thunderbolt Display. The most demanding part of my work basically involves using Adobe CS6 (mostly Illustrator, inDesign, and occasionally Photoshop). I'm not a graphic designer, but I do use the software fairly often. And, well, for the kind of work I'm doing in these applications... a quad core i7 and dedicated graphics just isn't necessary. So, I've ordered myself a shiny new 13" Air with the i5, 8gb of RAM, and the 256gb SSD. That whole "12 hour battery" thing is extremely appealing. I may finally feel like I don't have to tether myself to a wall outlet. And the prospect of hauling around 2.5 fewer pounds of laptop every day... yeah. Where the iMac is my new heavy lifter, the Air shall be my trusty sidekick. And, the Pro is posted on Kijiji.
I'm not knocking the "one workhorse laptop for everything" approach. I used to hate having to keep multiple computers more or less in sync, to the point that I opted for a single laptop. But, Dropbox has largely solved that for me. I have access to a giant dropbox account thanks to work, and I have literally ALL OF my files on it (Logic projects, Aperture Library, work files... everything). Now, keeping my iMac and Macbook in sync is completely effortless, and I can easily opt for two highly optimized machines, instead of a single compromised machine.
. Wondering whether the slightly slower but more efficient Haswell 1.3 GHz processor would make much of a difference to productivity (especially re photography) given the other gains.
