MBP Core 2 Duo vs iMac Core Duo

I don't believe that you'll see a big difference. In actual fact I doubt you'll see much a difference at all. Be aware that while the MBP will have a faster processor the iMac will use desktop components as opposed to the laptop components in the MBP.

The previous poster is correct. Because the iMac will be using desktop components, despite the increased processor speed of the MBP, apps like WoW will probably still run better on the iMac. However, as you can see from my Macintosh Computer profile, I have an earlier model 2.0 GHz MBP and I can tell you that even without 2GB of ram, which I have, it runs amazing. The 2 GB of ram just puts it over the top. And if you're still not satisfied with the frame rate, just run boot camp and install WoW on there. If I remember correctly, it'll run about 6 frames per second faster. In spite of this, I don't really like running windows, so I run WoW on Tiger anyways. And to be honest, it looks equally as good as my friend running wow on his gaming laptop. I don't even use an external display, so that'll be like the cherry on top. I guess all I'm saying is keep the iMac if you want, but I think you'd be equally satisfied and perhaps save some money if you used the MBP alone--with or without an external display.

I have never used aperture so I can't comment on that, sorry.

At any rate, Good luck with your decision

Actually, the iMac 20" Core Duo uses the same videocard (X1600 Mobility) as the Macbook Pro, so I doubt you're going to see a huge difference in game performance. The iMac also uses the "laptop-oriented" Core Duo chips (Yonah and now Merom) instead of the "desktop oriented" Core Duo/Core2Duo chipsets like Conroe, probably so they can fit it into that teeny-tiny midplane board.

A Core Duo MBP and a Core Duo iMac are pretty close to hardware identical; the only big difference I can think of right now is the hard drive (Since the iMac has a full sized 3.5" hard drive, it will be cheaper, larger, and usually faster, while the MBP has a 2.5" laptop hard drive), and obviously the iMac's monitor and the MBP's battery and portability.

There are some other differences, like slightly faster memory speed in the iMac and different part suppliers, but in general the parts that matter will be roughly equivalent.

While much of the components are the same you have the remember that the management of those components is wildly different due to a desktop environment rather than a laptop environment. You'd be surprised how a simple thing like power management can make such a big difference to performance.

And, as you mention, having a 3.5" drive is a huge avantage as they simply perform better. Being often a big bottleneck in system performance having a dektop drive is also a big advantage.

So, overall I expect them to perform much the same.