I think the most important factor is why you want to get into 3d. Most people agree that while MAX is gaining respect in the photoreal arena, it is still the preferred program for game development and other low poly/realtime applications. Maya/Softimage are used more extensively for work such as movie effects and the like.
Another factor is what the instructor is teaching. I learned 3ds MAX because that's what they teach at my university. I haven't used any other serious 3d programs, but I would imagine that once you have a solid ground in the theory and concepts of 3d work, the skills would more or less transfer over to different programs.
I couldn't tell you which is better, but since 3DS is used more often by your average 3D user over Maya, you might find more in the realm of support, plug-ins, forums, etc.
3DS is also supported by Macromedia Flash (if you ever want to exoprt Flash 3D files for the internet)
I would say learn Maya or SoftImage. What do you plan on doing with it? Game design? Also you do realize the cost of any of these programs right. The least expensive of these is 3d studio max which still costs about a grand even for the academic version which you are not alowed to use to make a profit.
Maya has better support for NURBS modeling, Max has better support for polygon (and subd) modeling. Regardless of which you pick, laying out UVs will be a complete pain in the ass.
Max 5's renderer is noticeably better than Maya's, but both pale in comparison to Mental Ray.
Maya tends to be less buggy, but some things in it (skin weights, for example) are done very poorly.
Maya's animation capabilities are significantly better than Max's.
Some of Maya's UI elements (HyperShade, HyperGraph) are much nicer than the corresponding elements in Max.