I've had first a Canon 350D six long (at least by technology count) years ago and with an 8MP sensor, it was really remarkable. Then a Canon 5D Mark II for the last four years (also a long time). I switched away painfully from Nikon back then. But now that the Nikon 800D is out and the Canon 5D Mark III is out, its time once again to think about the age-old Nikon vs. Canon problem. With all the lenses I have it would be truly painful to switch to Nikon. The glass is really what keeps you hostage and my theory was the two companies should be about on par which has been true for the last five years. But now with a 36MP camera in the D800 and the Mark III looking like a 22MP camera (maybe it should be called the Mark 2.1) plus with the exposure controls of the Nikon plus the rumored update of the D7000 to a 22MP DX imager
I'm really wondering what it would cost me to switch and get back to where I was with Canon. Here are my Canon lenses. Up until now I was thinking of doing a quick up date to the latest Canon 600D and then using these small lenses for the budding photographer in our midst:

• 10-22 EF-S. A terrific wide angle lense
• 18-55 EF-S F/2.8. Wow, what a nice sharp lense for normal work
• 18-200 Sigma. This is only a decent lense but it is a super zoom

Then for the full frame format I have the

• 24-104 F/4. This is my basic lense. Decently sharp. Not too fast, but in the old days when taking things at ISO 800 was amazing (as opposed to ISO 3200 like you can do with the modern imagers)
• 16-35 F/2.8L. I actually use this wide angle lense a lot more than you would think. Some really great effects here
• 100-400. Best for sport photography. While the 5D3 isn't the best sport photography system, I've gotten pretty good at it just by shooting alot and anticipating the shutter lag.
• 70-200 F/2.8. I actually don't use this lense as much as you'd think, but it is great for indoor basketball
• 50 F/1.4. I use this for low light situations.

So its quite a few lenses, knowing what I know now, what would it cost to get into Nikon then. Maybe the answer is to keep the glass and then I don't really care who wins Nikon or Canon 🙂 as Ken Rockwell says...

• 50mm F/1.4 AF-S. $400. Low light like the Canon • 16-35 F/4 VR AF-S.$1200. Not as fast as the professional 17-35, but less of an issue with a wide angle IMHO.
• 24-70 F/2.8 AF-S. $1.8K. Interesting, he doesn't recommend this one, use a 50MM instead and walk because the zoom range is too narrow. Or get a discontinued 28-108 AF-D • 70-200 F/28 VR II. This is the goto sport lenses in low light although the$500 70-300 VR is fine at $500 for bright light (and with cameras being so fast maybe this is less of an issue). • 135MM F/2 DC. The perfect portrait lense So quickly here are some of the reasons to stick with Canon and see what they do with the Mark III or their upcoming updates as noted in the fanzine, Canonrumors.com • Jeff. He's a Canon Explorer of Light, so probably not unbiased, but as he says, 22MP is all most folks need and file size is a decent compromise (hmm....). The viewfinder and AF system are much better than the Mark II and it is two stops better than the Mark II (so hopefully I can go from my normal ISO 800 as the max to an amazing ISO 3200!). • Ryan. Yes, it's an incremental upgrade, but the fixes to the Autofocus • I can keep the glass I have and spend the$2.5K instead of that wonderful 85MM F/1.2 lense and 135MM F/2L  I've wanted 🙂

The reasons to finally switch are that the D800 sensor is pretty incredible. The #3 sensor in DxOmarks right now with only medium format cameras ahead of it:

• 14EV+ of dynamic range in the new D800 sensor. Wow that is pretty amazing
• 36MP of course

And the reasons to wait are that Canon is about to introduce a 4K DSLR, that is being able to take movies at full 22MP (that is 4x Blu ray!) using 35mm lenses which is coming next year. Now that would be some camera!