CTR: A few specific questions...

[Stefan_G]

-It sounds like the water filter is a "must" have.  The piece of mind it affords you is worth the extra few ounces.

If there is plenty of anything along the CT, it is water!  The longest stretches *on trail* without are from Sargents Mesa (Tank 7 creek, 12 miles into segment 16) to Lujan Creek (20ish miles into Segment 17).  And then from near Spring Creek Pass to beyond Carson Saddle.  While it's not actually that far, these are long and difficult miles.  In 2009, I rode with only 3 water bottles, and I was pretty thirsty through there, especially after a bivy.

I did not take a water filter, but I had a gnarly case of Giarda when I hit Durango.  IMO, it's a tough call.  So many of the water sources are high enough to be completely clean, but it only takes one bottle downstream of a big cow pie to cause some serious damage.  I've always felt that a filter was king because of the speed and ease at which you can get clean water, but I think a Steri-Pen would be a fantastic alternative.  Super light, and you only need to use it on questionable sources.  Tablets are even lighter, but ya gotta wait...

Good luck in 2012!

[JReeves]

Thank you guys for all the input!  I've made a few moves gear wise, to get ready for this trip.  With my cook kit lightened, I moved to my sleeping setup...  Just ordered a WM Summerlite bag(1lb3oz), got a Thermarest NeoAir a couple weeks ago on clearance, and also scored 3 yards of eVent fabric that I'm going to use for the top material on a bivy.  I'm going to keep it pretty simple, using lightweight silnylon on the bottom, the eVent on top, with a nano-see-um mesh panel for bug protection.  The bike frame is nearing completion, and will be in my hands at the end of February!  I have a majority of the needed parts to get it together already. 
-Wheels are something I'm still considering.  I love my Easton XC One SS set, but the 24 spoke count has me considering something beefier for the CTR.  At 185 pounds loaded, I'm still by no means a "clyde", and reviews on twentynineinch.com were positive for these, even with both test riders weighing in at over 200lbs.  Is this something I should be concerned about?  I'd love to put the money elsewhere.
--Tire wise, the Ikon's sound like they're worth a try, and if not, then the Ardents still have my attention.

-A GPS might be a purchase I make in the next few months.  The only real negative is obviously the extra expense, but saving hours of effort in the event of a mistake in navigation could be well worth the cost.  12+ hours into a day, following a line on a screen sounds much easier than trying to decipher the trail at a fork...