Fred,

If I were you, I would look into the SRAM Red TT group if you can with return to centre TT shifters.

Failing that, I would probably go with the full DA build (however, my bikes are all some combo of Tiagra, 105 and Ultegra).

Sounds like a great upgrade, I really like the Transition Pro, especially with a Virtue Bottle as a flat kit (or water bottle) as it essentially fairs the BB area.

Shane

Sram chain and cassette with Zipp crank.  Just what I'd personally want for no other reason than I've never had a problem with my Sram chains an cassettes and I've always wanted a Zipp crank.  Oh, and if possible, be at the shop for as much of the build as you can.  It'll be an awesome learning experience.

More importantly about your old frame.  What size is it and what are you doing with it?

My opinion.

1.  If you’re getting a GREAT deal on the 2008 Specialized Transition Pro frame and it’s mint or super low mileage good start. 
2.  Zipp VumaQuad Crank too much $ for the bang.  Your bang is in your legs so a Red or DA crank will do fine.
3.  Easton Crank unsure but see #2.
4.  I personal would do a Red build #1 then the new DA group #2. 

For the Aero bars best fit wins but if it these: http://www.eastonbike.com/PRODUCTS/BARS/09/bar_road_attackTT_'09.html

I think the size is limited to 38cm width and the Reach Range is not so adjustable you have to order your range.  Then there are these Eastoin Attack bars;  http://www.eastonbike.com/PRODUCTS/BARS/bar_road_attack.html  So not sure which ones you had in mind. 

Here is a nice new option;  http://www.profile-design.com/profile-design/products/aerobars/carbon-aerobars/cx3.html  That is if a 42cm width is your size.  Too color choices

I would think you want aero bars similar too the one you rode this year at LP.  You’re going all carbon?

Hope it helps. 

EDIT Link fixed

The one thing you need to consider here is the Easton bars are not as wide.  Also compare the flexibility as I would think flex could be a issue.

I have not heard any durability issues or crank issues.  Mixing components can be tricky so I do suggest staying with all the same components.  I have tried the SRAM TT carbon shifters on my Ultegra group and had issues fine tuning the shifting.  Switched back to the DA shifters and did the IMLP without issues.  You may consider the wheel you have now.  They are Shimano hubs right?  Will the cassettes work with SRAM?  I have no experience with SRAM and Shimano mixing components other than the shifters as mention.

I have test ridden the new DA stuff, it is urber smooth and stiff.  Friends have said the same.  So if the real issue overall compatible components mix ie crank issues on that frame than the safe bet is the DA.  At the level it all is good. 

You can research weights at Weight Weenies; 

http://weightweenies.starbike.com/

But you shouldn’t be too concerned about weight when getting into high end components.

SRAM Red 10-speed Components Kit