It doesn't sound like you are too locked into Nikon lens wise, so don't feel like you have to write off the Canon option. The digital Rebels are all great fully functional SLRs, even the old 300D.
Honestly, if I were working from scratch, I'd buy the cheapest body I could and a Tamron 17-50mm 2.8 to go with it. Like I said before, the real advantage to going with a DSLR is the selection of good glass options that comes with it. A good lens is seldom outdated and is a much better improvement compared to getting the latest, greatest body.
Schmitti, I think they have found that anti-shake lenses are more effective than any in body system. I know that the latest Canon IS lenses are advertised as being good for up to 3 stops. Sony's in body system could never hope to match that, especially not on long lenses.