There was a discussion about a possible, but highly unlikely, extension of I-45 out of Texas and through Oklahoma and Tulsa, here:
http://www.tulsanow.org/forum/topic.asp?TOPIC_ID=1619&SearchTerms=I-45
In the transportation bill that has passed Congress and is expected to be signed by the president, there is money for projects on I-49 - which is slated to run from New Orleans to Kansas City, through western Arkansas. Some of the funding includes $37M for an I-49 bypass in Bella Vista, AR and $200M to complete I-49 from Shreveport, LA to the Arkansas border.
Even if it takes another 20 years to fully complete this route, it shows the continuing maginalization of Tulsa (the overdue I-44 expansion in Tulsa is only receiving $118M).
The I-49 corridor, when completed, would allow traffic from KC, St Louis, Minneapolis, and Chicago, etc. that is going to Texas, to bypass Tulsa (and OKC) by going south on I-49 and taking I-30 into Texas. The I-49 corridor also benefits Wal-Mart and several of the large trucking companies based in NW Arkansas. Arkansas' reservoirs and hilly country would also benefit from tourism with a direct highway route from Texas/Louisiana.
With no major cross country highways crossing though Tulsa (like I-35 and I-40 in OKC) and airports like OKC and NW Arkansas squeezing Tulsa for direct flights, Tulsa is going to have an even harder time securing new business development. About the only minor redeeming transportation factor is the Tulsa Port of Catoosa. But, given Tulsa's lack of foresight, Ft Smith will expand their port on the Arkansas River when I-49 is completed - thereby completely acing Tulsa out of the transportation biz.