I'm now seriously considering buying a Canon XS body (I've found it for $350, give or take a bit), and then getting the Sigma 18-200mm OS lens. I've looked for a lot of things, and I think I'm finally settled. I'd take a D40, but the XS is only a bit more. The next step for me above an XS would be a Nikon D80 or Canon 30D, but both of those are considerably more.
As far as lenses go, I'm figuring I'll just spend my money up front--I've heard that lenses are a worthy investment, as they depreciate much slower than bodies do. I looked at the Canon 18-200mm IS, but it is a considerable amount (ie, $450ish) more than the Sigma (~$300), while it supposedly isn't too much better.
So, either tell of your objections or forever hold your peace, jk