I feel like the Chicago - St. Louis "High Speed" has become a sinkhole for money with very little to show for ti. A lot of that is Illinois politics. The reality is that in GM&O days regardless of speed limits of 79 mph or whatever, the schedule was likely faster than the best now and little slower than that after the 110 mph is in place. As a matter of pride the GM&O boys did their best to keep schedule even if it meant running 90 plus regardless of speed limits. Then at that time there were three railroads operating Chicago - St. Louis passenger service.
I think the reason you have seen little to show for the CHI-STL corridor is that they still have a long way to go on the improvement projects. Checking the status of the big $1.142 billion grant on recovery.gov (diving down to state and projects), IL has filed their quarterly report through December 31, 2013 which shows that $370 million of the total grant has been spent so far (link which may not work). The $1.142B grant includes rolling stock purchases for the corridor service, so those won't be paid in full until the bi-level and locomotives are delivered. Still, as a crude metric, IL has spent 32% so far of the major grant for the corridor upgrades for the bills that were paid as of December, 2013.
There is a separate $186 million grant for double tracking and upgrades from Dwight to Joliet, which I believe has yet to start any track work. It is a FY10 project grant, so it is not covered on the recovery.gov tracking site. While the CHI-STL corridor will need another billion or two to reach the final project goals, the improvements from the funding that has been provided are still in the pipeline. Have to give it until at least 2016 before the funds are going into a sinkhole or not. Yes, this is taking a long time after the funds were awarded, but unless you are DOD, it usually takes time to spend some $1.4 billion in federal money.