As a tulane MS4, I'll give you my 2 cents:
I would say that Tulane has a solid program, the best in Louisiana in my opinion, however, I'll admit that I know NOTHING about the Shreveport program. The PD at Tulane is FANTASTIC. Awesome teacher, in and out of the OR, and an excellent student and resident advocate. He definitely looks out for the residents, and helps those who want to pursue fellowship--all the residents I've spoken to have attested to this. Overall the staff is hit and miss when it comes to teaching--not much different than most programs around the country I would assume. Residents have lecture every morning at 630--most are very good IMO. Cases start at 715-730. I think that the caseload is pretty decent. Peds seems strong, they do a fair number of liver tx, cardiac is pretty weak--all residents rotate through Houston (TX heart, I think). The schedule seems pretty avg as compared to what I read on Scutwork, etc. Basically 6am to 5-7pm. Call is done by nightfloat--4 weeks/year, divided into 2 wk segments, i think--so no overnight call. As far as atmosphere, the residents seem to all get along VERY well and seem VERY happy. They are a very fun, laid back group. The younger classes are about 80/20 US/foreign, older classes more like 50/50. Overall, a solid program with great residents, decent teaching, and an AWESOME PD.
Shreveport--don't know anything about this program.
Ochnser--I don't have firsthand experience, but what I have "heard" is that it is a "cushier" program. Most residents done by 3, and if you stay late I think you get paid for overtime. Residents may have more exposure to cardiac cases, since I know that Ochnser does more hearts than Tulane. Teaching is definitely weaker there--attendings there tend to be more interested in making $$$ and going home. Seems to be overall a weaker program than Tulane.
Hope this helps. Feel free to PM me if you have more questions.