I'm getting very long load and turn times as well, but save times are fine. Tests run on turns 653-655, epic, huge, max civs, 18 city states:
Save: > 3 seconds
I do not have the bloated save file problem, as my save file is around 1.5mb. System:
CPU: Intel(R) Core(TM)2 Duo CPU T6600 @ 2.20GHz
GPU: NVIDIA GeForce GT 230M (1GB dedicated)
Thoughts? Am I just screwed when it comes to huge maps in the late game? I get similar results on my second machine, which is a desktop with similar specs.