I'll be buying Aperture when the campus bookstore gets it, and I'll report back how it runs on my wife's 1.5GHz G4 laptop. My current 1 GHz G4 laptop (and probably yours...) doesn't have a GPU that handles CoreImage well. I imagine it is going to be slow, but I can live with it till the dualie gets here
Nothing another $10K can't fix...
I'll be trying it on a 1.33 GHz iBook when a friend buys it in the next few weeks (it won't be in stores in Australia for about a month). If it works on his, I might buy one for mine. Think I might need to run an external monitor tho - I'm guessing it might not be optimised for a 12" screen. The GPU in my iBook can handle CoreImage apparently.
Supposedly the key rquirements are that your computer supports core image. I have read that you need 128 mb of video ram. However my desktop has a video card that apple says is good enough but only has 64 mb of video ram.
PDN Online has a "closer look" article on Aperture that is quite interesting. One of the things explicitly mentioned is the IPTC export situation, which at first glance looked like it will be a problem, but apparently it will not.
Still no curves function though Herb, they seem to think you're better to pop out to Photoshop for that
Here is another good article on Aperture discussing pros and cons...