I'm going to build a new PC that'll mainly be used for graphics & 3d programs like Photoshop, Maya, After Effects, Illustrator, SolidWorks, etc. I'm trying to build something that I could upgrade in the future. It seems like AM3+ might go away in the next few years. LGA 2011 seems like it might be around, but it's really expensive. LGA 1155 is somewhat new but I'm not sure how long it will be around. If I wanted to upgrade memory and replace a chip a few years from now, which socket seems like it would be the best way to go? Is Intel still going to release a Core i7-3980X eventually?
LGA 1155 is already dead by release of the original Ivy Bridge line of CPUs. LGA 1150 will be the replacement socket due later this year IIRC.
AM3+ will last through at least the release of the FX-X5XX series processors. By process of elimination we can determine that this socket has the potential to last the longest out of the above three. However AMD is likely also turning their gears in getting a new socket ready (DDR4 and such).
well go with what you feel is better in ur point of view example what you like better Amd or Intel its ur money ur time ur build lol just pick what makes you happy seriously its ur build if you want intel wait teal the newer mobo comes our if you want Amd go with a phenom ii or a fx series XD
+1 with what Jayy said. To expand on my post, all three of the sockets you listed are very near the end of their service life (almost equally) so don't base your decision off of socket lifespan. If you need to upgrade the CPU in the future, you will probably also get a new motherboard anyway.