Hi Aaron,
The D90 is very nice, my friend has one and its what prompted my thinking about getting something new! The AF system is excellent, I used it to take some photos in a situation where my E510 was struggling and it was brilliant but I find it really difficult to hold. For me its really quite heavy and the body is just that little bit too big for me to use one handed.
I went into LCE the other day and tried a k7, which is about the same weight i think and it was much easier to hold for me.. my total budget, because I am changing systems, is about £1500 for camera plus kit lens, one reasonably long zoom (compared to my 40-150 anyway!) and a macro (havent budgetted for bag/battery/cards yet....**sticks fingers in ears and goes "lalalalalalala"**).
I looked at some of the Pentax k5 bundles which would get this if you added a 50mm macro on top but I am not sure if the Pentax AF system is as good as the Nikon one....but the k5 does look very nice and as I find the D90 so difficult to use...
The alternative is a Canon 50D which is also good for me ergonomically but I havent looked much into pricing for that one, it seemed more expensive from a cursory glance the other day!
decisions decisions!
Thanks for your reply though, its great to hear where other people have gone to from where I am now!
Julia