If you are shooting landscapes and portraits, why do you need faster AF than the 5DII provides?
Short of the 1Ds MkIII, you aren't going to do any better than the 5D2... For your type of shooting.
7D is designed primarily as a sports/action camera. You say you're not a sports shooter, so doesn't sound like you need it.
7D and 5DII compliment each other in some ways, but not in others. They share batteries and chargers... Control layouts are similar (7D has some add'l buttons). But once you are shooting, working in the menus, using the AF, etc., the 50D and 5DII are actually more similar.
I agree with a couple other posts... New, different or better lenses will do a lot more to improve your shots, than any new camera body can.
Mainly a portrait shooter? Buy a 135/2 for use on your 5dII.
Landscape shooter? Might want some wide primes. And/or a nice tripod.
Need two cameras for some reason? A second 5DII would be your best bet for the type of shooting you do. Or just keep the 50D.
I don't find 5DII to be "miles ahead" of 50D at all. In fact I've made images with 50D that I was certain I'd shot with 5DII when I was making prints from them, until I looked at the EXIF and saw that I'd used 50D (usually with one prime or another). Micro adjust your lenses on both cameras (primes are much easier to MA well, than zooms are). Avoid under exposure, use reasonable ISO settings, and the 50D can shine very, very well.
The main "upgrades" 7D brings over 50D are: more AF points to work with, a bit bigger/brighter 100% viewfinder, slightly faster frame rate, more focus modes that are mostly designed to work with specific action situations (exception: precision AF mode, good for macro & portraits, but slower), increased sealing and durability, 63 zone metering system, and a few other things. 7D has the finest spot metering of any current Canon model, but the 5DII is very close. 7D is a fine camera, but IMO the 50D holds up very well in comparison... Unless for some reason you really, really need your still camera to be able to shoot video.
Besides, I suspect that we'll be hearing about a 60D any day now... And I bet it will basically be a 50D with video capabilities added.