I also just noticed that in CF11 when setDomainCookies = true (as described above), the CFID value is a really long string like this: Z878pt2v0jgtx8yvvdf8rr3ifl19dswl61juevwo42y6ibcn65-1168 instead of the normal short, numeric value. Also, this CFID closely matches the value for the CFTOKEN cookie: Z878pt2v0jgtx8yvvdf8rr3ifl19dswl61juevwo42y6ibcn65-59bcdaab076aa06-2997ED3A-C291-54C7-53D0BF27179FEDC9. Looks like there's just a long (and same) prefix in both cookies... never seen this before.
When I set setDomainCookies = false, the CFID cookie goes back to the normal short numeric value (no prefix).
Thought it might be worth menitoning...
Dan