They're both comparable cameras, one is newer while the other is a bit more tougher built and has some extra stuff like more focus points and faster fps. But photo quality wise, they are the same sensor size, probably have similar low-light performance, both does HD video at 24/25/30 fps for 1080p and 50/60 fps for 720p.
I don't think you'd regret buying either one. Just look at your needs. It's not like you're comparing an APS-C to a Full Frame camera. Looking at the price on Amazon UK there is a difference of about 250 GBP.
You said you do macro photography, so is most of your work done indoors in some sort of studio or make-shift studio set-up? Or are you going out in the woods, mountains, etc with a tripod with a bigger risk of your camera being damaged by the elements?
Action, sports, motion: go for 7D due to more focus points and faster fps
Landscape: either but preferably 7D due to better weather sealing and tougher build
Lowlight: either should be fine
Indoor photography: 60D to save money
Portraits: either does fine, the only cameras better are full frame and larger sensors
Consumer usage: 60D, save money with the economy the way it is today (SD cards are cheap), or keep using your old camera to save even more money
Video: either should be fine, ask Philip Bloom for advice or look at his blog: http://philipbloom.net/2010/12/07/whichdslr/
Vacation photographer: buy a cheap camera or second hand or use your old one, just in case you end up losing your camera, it gets damaged or stolen etc while you're on your trip.
Are you into extreme sports: do you want a lightweight camera to reduce the total weight of the gear you are carrying or do you want a tough camera that can survive your extreme delights?
Work for National Geographic? Or other NGOs? Travel to places like Africa, Asia, etc to take photos for documentary or other professional purposes: Why are you bothering with these 2 cameras, go look at the Nikon D3 series or Canon 1D series.
And remember to get your gear insured.