First, if you are new to DSLR Photography and you wish to buy a new camera, then you are spot-on and I won't repeat the wealth of information the other kind reviewers have already given. I'll just focus on why D40 users need to upgrade.
Second, I dont recommend D40x users to upgrade to this model! true the new futures are a plus however, personally I find it not a big difference. unless you like to keep up with latest technology releases and don't mind paying the extra dollars :)
D60 have the upper hand due to some of the following these features;
- Active D-lightning (No more underexposed photos).
- The new Expeed sensor (as in the D300, reduced ISO noise)
- The new VR Lens which produce sharper images.
- The Dust reduction is a big plus
- supporting 4GB SDHC cards.
I highly recommend this camera. When I bought it I actually had people stop me and say "I have that camera I love it!!" the cashier said "we sure sell a lot of these!" May I also mention it was NOT a electronics or camera store so I think that is saying a lot! :)
And if this's your first DSLR,you should buy with Accessory Kit.
Nikon D60 Digital SLR Camera with Accessory Kit
KIT INCLUDES 8 PRODUCTS -- All Brand New Items with all Manufacturer-supplied Accessories + Full USA Warranties:
<#1> Nikon D60 Digital SLR Camera & 18-55mm VR Zoom Lens Outfit PLUS
<#2> Transcend 16GB HC SecureDigital Class 6 (SDHC) Card
<#3> Spare EN-EL9 High-Capacity Lithium-Ion Battery Pack
<#4> Nikon SLR System Case
<#5> Precision Design USB 2.0 High Speed SecureDigital (SD/SDHC) Card Reader
<#6> Digital Image Recovery Software
<#7> Precision Design Memory Card Storage Wallet
<#8> Cameta Microfiber Cleaning Cloth
Price: $579.95 + $18.95 shipping
reference: http://www.amazon.com/Nikon-D60-Digital-18-55mm-Accessory/dp/B001JDL8M6/ref=sr_1_10?ie=UTF8&s=photo&qid=1235928658&sr=1-10&tag=commentglitte-20&linkCode=ur2&camp=1789&creative=9325
Hope that help.