I can't answer that question for you but I answered it already for myself. I DO NOT want a DSLR.
I paid around $300 for my Kodak P850. It has 432mm zoom (and upwards of 700mm with a $100 attachement). The image quality is not perfect, but it is very good. It is 5MP and unless you plan to blow the pictures up VERY big, the quality is fine.
Now if you want to do everything the Kodak P850 does with a DSLR, you will end up paying at least 6x the price for the camera body/lenses/etc. and thats if you get good deals on lenses that arn't the best.
If I were to upgrade my camera right now, I would get the very best prosumer camera on the market, but not go up to DSLR. It just isn't worth the money to me. In my opinion, a DSLR is either for professional photographers or for people to whom money is simply no object. If you can get something for $500 that can do close to everything a $2000+ DSLR does, then I am taking the $500.
Now again, this is really dependant on you. Do you have money to burn? I sure don't, but I'm 15 years old. Do you plan on making huge copies of your shots? For 4 x 6 inch prints or even bigger like 12 x 18, you won't see much of an advantage.
I also have to point out one major weakness of Prosumer cameras compared to DSLR (especially my prosumer). This is the lack of wide angles. Prosumer cameras rarely have an angle wider than 24mm or so. With DSLR you can get relatively cheap lenses ($500-$600) that offer you shots at 10mm. So if you plan on doing lots of landscape work, then a DSLR is the way to go.
DSLR's also have FAR superior low light performance. This could be useful if your son is ever playing football in a dimly lit stadium.
Sorry for the long post.
You should check dSLR and lensprices. I sold my P850 and bought the *istDL kit for less than I paid for the P850. I added a 28-300 (42-450 equivalent) zoom for another $130. You can
spend hundreds (or eventhousands) for lenses, but you don't have to. Plus with the change of a lens, youcan have a completely different camera.
Also, the 5mp of the Kodak (or any P&S except the Sony) comes on a much smaller sensor, meaning muchmorenoise at low lighting. The Kodak took some nice shot in the dark, but Ihappened to takea similar shot with the DL (separate trip, different time of day)and was amazed at the difference in detail. Kodak has some nice noise reduction built in and shoots nice shots. However, I think the DL has much wider dynamic range, meaning the highlight details are more visible. Both are nice, I just like the dSLR better, and the price isn't that much more.
Kodak P850 shot:
Pentax *istDL shot: