My main photography is wildlife and landscapes. When the 5D MkII was first released, I considered it as a replacement for my 40D, but I didn't because of the wildlife aspect. Then when the 7D was released, I checked the first RAW images available, compared the amount of noise relative to the 40D and jumped in with a pre-order, keeping my 40D as backup. As a wildlife camera for someone on a budget, it is difficult to beat, however, I immediately saw its weaknesses when photographing landscapes. It can certainly be used as a landscape camera, but it needs a lot more care, with hyperfocal distance and at narrow apertures, diffraction is obvious. After about 10 months, I decided to get a refurb 5D MkII purely for landscapes and it has given me a lot more flexibility in landscape photography and has helped me progress through experimentation and the confidence that the camera will provide the IQ I need. I don't use it just for landscapes however, I often turn to the 5D MkII for macro work, because of the IQ and also because I find it much easier to focus manually with it than the 7D. Also, when the light levels drop, I also use it for low light wildlife, for example, last year, I used it to photograph woodcock roding around 40 minutes after sunset, using centre point focus in one shot mode. It certainly isn't a sport/action camera though. I also used it to photograph diving gannets and that was an experience to say the least (I had concerns there was something wrong with my 7D at the time). I managed to get shots, but it was a single chance on each dive, so I had to anticipate every moment and try to time it right. That's fine where it is more or less predictable once the dive has started, but for more unpredictable moments, it just wouldn't get the shot.
So whether your friend goes for the 7D or the 5D MkII probably depends on whether he shoots more landscapes or more sports. Overall, the 7D probably has the slight edge as an allrounder, but also consider, that the cost of the 7D and 5D MkII together are still slightly less than the 5D MkIII.