I've not used either so I'm going on specs here Haggler, but I'd feel more comfortable with the 5000 as it's a much chunkier bit of kit all round. I do like CMOS chips too. I find them smoother and a lot less noisy than a CCD. The 5000 has about a stop better low light capability and the focussing is far superior to the 40. But without using them both, that's the best I can do, I'm afraid.
My dad got an 18-200 this year and he's been loving the results - it's a really versatile lens. It's also worth looking at getting a 50mm prime for your bag. The 1.8 is a great lens (£80) and if you can, the 1.4 (£240) is even better. They're super fast - about 2 stops faster than the 18-200, and great lenses to use for general walking about. Because they have less glass in them (fixed focus), even more light gets in and the quality is better/sharper. Worth having a look
