Bernie Meyers of IBM once told me that he believed FPGA would be the future of Moore's law. he felt strongly that they provided a performance and flexibility tradeoff that made them ideal for using in virtually all servers as coprocessors for certain functions. The fact that the FPGA code can be audited was a plus as well.

FPGAs start from far, far behind on the performance end though (by a factor of several dozen). FPGA vendors compete to shift as much as they can out of configurable logic and into lithographically-defined IP blocks because of this severe disadvantage. A modern FPGA will be strewn with hardwired serial interfaces, memory controllers, CPU cores, and the like. Taking advantage of these is almost always a gigantic performance win, and that's assuming the functionality they provide is even possible in configurable logic (e.g. try implementing a 32Gbps serial port using only configurable 500MHz logic).

FPGAs don't trend towards openness and you have to get a 100x win from their flexibility to break even on performance.

I'm curious about what Intel will do now that they own Altera. Maybe they'll be able to push FPGA technology into mainstream CPUs.

Not sure about economics, but separate PCIe card with FPGA and it’s own storage is not that hard to build. Such setup could accelerate big data operations for sure.

You can audit the FPGA code but good luck auditing the bitstream and those tools are all closed. Even for a small FPGA this would be quite a task.

I've never actually priced out an application where FPGAs were competitive on raw compute power -- GPUs have always smoked them for the tasks I was interested in, and not by a small margin. We only ever used them because they were "hardware engineer duct-tape" -- they let us talk to chips, network, and system busses at high bandwidth / pin count. Real time pipelines were a bonus but memory and compute were so much cheaper on computers that buffers + overprovisioning were a much more attractive real time solution wherever the logistics weren't prohibitive. Often they were, though, forcing us to use FPGAs for compute even though they weren't particularly good at it.

I have a sneaking suspicion that this is a more general truth and that in many applications where FPGAs are touted as compute accelerators they were actually chosen to minimize the length of the critical real-time data path rather than to do more computation for fewer dollars.

It's surprising how many places FPGA's show up. I picked up a used black magic pci capture card that had a xilinx on it. It's not a mass consumer product but I am guessing they still sell a good number of them.

People seem to forget that much of the allure with FPGA's is the 'Field programmable' part - where you can fix bugs and upgrade hardware after it's shipped.