These processors really are quite similar in performance, and I have had great luck using both in multiple computers.
The strenghts of the i5-760 processor is that it can automatically overclock to about the same base clock speed of the Phenom II X4 955, but that's only with one thread so it honestly doesn't happen much when you're working with most of today's software. It also has a lower power usage so will run a little cooler than the AMD processor. Really the area where Intel processors are the best bargain is if you plan to do some major overclocking to get a higher clock speed out of them, but it doesn't sound like you want to do that.
The strength of the AMD Phenom II X4 955 on the other hand is that it has an obviously higher base clock speed. It does have a slightly higher power draw but with an aftermarket CPU cooler you can get very cool running temperatures. I've used the Cooler Master 212+ on both of these processors and it has worked wonders to keep things cool on both systems. The AMD processor seems like a real workhorse and never bogs down even when I'm exporting 1080p video conversions from Adobe Premiere CS4 and that's why I chose it for my home
computer back when it was the AMD flagship processor.
You shouldn't have any problems with them working with your software, either way they are going to be pretty much equal in performance in the end. Even though you mention that prices aren't part of it to consider, it really is something that means a lot in the end. You're going to get more features and better performance from the AMD platform for less money than a comparable Intel platform: The processor prices are less and the motherboards can be less often times, too.
Since solidly picking one processor over the other is hard for me I'll give you a motherboard to match for each. With an Intel processor I would choose the ASUS P7P55D Pro or EVO for an ATX motherboard or P7H55-M Pro for a microATX motherboard. As for an AMD system I'd say the ASUS M4A89TD PRO for an ATX motherboard or ASUS M4A88TD-M for a microATX motherboard.
A couple things to keep in mind I guess:
1) If you aren't planning to overclock the processor, the AMD Phenom II X4 955 might have a slight advantage, not only because of cost but because of higher base clock speed.
2) If you aren't sure your case will have good cooling or you aren't planning to purchase an aftermarket CPU cooler, the Intel Core i5-760 migith have a slight advantage as it can run a little cooler. If you plan to overclock the processor this one might have a little more headroom to get a higher base clock.