The only ones I am going to have a little issue with you are on the above points which were true in the early days (maybe a year or two ago) but are not as true now:
1) Fast focusing... The newer Prosumers are pretty fast .. My A2 is running faster thanmost Nikon lenses on D70s and D100sin the same situation and is keeping pace with Canon stuff. The USM Canon Pro-1 is fast also.
2) Depth of field... Good point, but you still lose a little with the smaller CCD of the standard (non-full frame) DSLRs. Not as much but it does take some getting used to.
3) Lenses as an investment .. True but you have to be careful, the newer lenses are being marked digital and if the future camera has a full frame CCD they won't work with it. Also I imagine a lot of Olympus fans are deciding if the 4:3 stuff will be an investment or the next screw mount lens
Also even if youhave an existing investment you will probably need to buy a new wide angle lens since your old WA is now close to a normal lens. Good news is you probablyhave a great"new" telephoto.
4) Speed of writes.. Well the newer Nikon D70is a speed demon for writing but the 10D/300D/1Ds Canon is about the same speed as the A2. The Nikon D100 is not that fast either. So the rule is more like speed of the Prosumer is about one generation slower than the DSLR.
One that you missed is the DSLRs tend to have a bigger buffer in the camera so they can do more continuous frames (at full size) than the smaller cameras, The ultimate being the Kodak DCS having 512M of buffer space.
You're right. That's whyI used the term "most" in front of DSLRin some of the text regarding focus speeds and write times.There are always exceptions.
The "prosumer" (non-dslr) models are getting much better at some of these functions (focus speeds, etc.). But, then again, the newer DSLR models like the D70 aren't "standing still" either (as you noticed, too -- since you mentioned that Prosumersseem to be "one generation slower" than the DSLR).
Good point on the "crop factor", too. Someone used to a 35mm SLR, may not like the way their lenses work on cameras with a 1.5x or 1.6x crop factor (because of the crop factor impacting "35mm equivalent focal length" -- especially since the actual focal length of the lens is what impacts Depth of Field).
As far as the new 4/3's system and lenses...I did mention this in my first post in the thread (since the original poster was looking at Olympus):
"This model (Olympus E-1) is using a new "4/3" System, and requires lenses specially designed for this format."
You're also correct on the new "digital only" lenses coming out for other models. This is probably going to get pretty confusing to many users (especially if they want to use both 35mm and Digital SLR models with their lenses).
Great Points! I was just trying to give the original poster some insight on the major differences (in case he really didn't mean SLR).
Thesewere just some "general observations" , intended to compare most non-DSLR models, to most DSLR models.