To be honest I was looking forward to the mid range model with discreet GPU as well but from what I can tell there's no reason for it (except maybe gaming). I don't know what benchmarking tools are up to date but here's a comparison of XBench on the 4 macs I have access to. I ran the Quartz Graphics test, OpenGL Tesst, and UI Test. Numbers below are the combined output. If someone has a better test for me to run I'm more than happy to. Since all but the 2010 mini are notebooks I used the native resolution (e.g. what they were designed for). In the case of the retina MBP you'll see results with integrated and discreet as well as retina and non-retina resolutions.
13in mid 2012 MacBook Air 2.0Ghz dual core i7, 1440x900, Intel HD4000, 512M VRAM: 351.24
13in early 2009 white MB Core 2 Duo, 1280x800, GeForce 9400M, 256M VRAM: 74.26
15in retina MBP 2.7Ghz quad core i7, native retina resolution, GeForce 650M enabled, 1TB VRAM: 181.27
15in retina MBP 2.7Ghz quad core i7, native retina resolution, Intel HD4000 enabled, 512MB VRAM: 215.80
15in retina MBP 2.7Ghz quad core i7, native (non-retina) 1440x900, GeForce 650M enabled, 1TB VRAM: 371.35
15in retina MBP 2.7Ghz quad core i7, native (non-retina) 1440x900, Intel HD4000 enabled, 512MB VRAM: 315.08
2010 MacMini 2.5Ghz dual core i5, 1280x1024, Radeon HD 6630M, 256MB VRAM: 312.38
Out of all of these machines the MBA with intel HD4000 is the winner. One odd result to me is that the Intel HD4000 actually shows better performance on the retina MBP over the GeForce at retina resolutions. Maybe that's true based on the type of test Xbench is running or maybe a bug in Xbench, who knows. Either way I'd expect low scores on the retina MBP because of all the pixel doubling/scaling/etc. going on.
All tests aside the 13in mid 2012 MB Air with a 2.0Ghz core i7 processor and integrated HD 4000 graphics screams. This is actually my girlfriends machine. It's used roughly 12-14hrs/day for work; 8-10 of those it's hooked up to a generic 1920x1080 DVI monitor as the primary display with the MB air display as secondary. I've never seen it lag in normal day to to day use. This includes Pandora on the air display, a copy of Parallels with Windows 7 always running (including aero) for WordPerferct and other apps, Outlook with a 10+GB mailbox, Chrome with 20-40 tabs, and Apple Mail open for personal mail. All animations in both Parallels and OS X are fluid and there are no delays whatsoever. If I didn't know better I'd think I was on my retina MacBook pro that cost twice as much.
Bottom line, I've always hated integrated graphics, but the HD4000 coupled with Mountain Lion works *very* well. I plan to use my mini as a media server so the core i7 quad (video encoding) and USB 3.0 (storage) were way more important, however I do plan to use the machine on a daily basis with generic 1920x1080 DVI display and don't foresee any issues based on what the air can do with only 2 cores and a 2.0 Ghz processor. I suspect the mid-range mini with 4 cores and a 2.3Ghz processor will perform stellar in any application except maybe intense gaming.
To all the complainers: stop jumping to conclusions so fast and do some research. The mini is a phenomenal machine for the money and if it performs just the same with one less part that means less power consumption and less heat in my office, I'll take that any day. Connectivity wise it maintains Firewire 800 while providing 4 USB 3.0 ports and ThunderBolt; that's huge for a machine starting at $600. The addition of USB 3.0 alone makes the upgrade worth it if you plan to connect any external disks.
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If you have a GMA something, it will be a huge leap. If you have a 9400M, it won't be that huge.
See my above response. I thought the same thing but check on the difference between the 9400M in a white MB vs HD4000 in a MBA. It's gigantic.
