What edge does Linux on a PC has over Solaris on a Sun Box?
Fair question. I think the answer goes something like this: How much money does Intel sink into R&D each year? How much money does Sun sink into R&D each year? As long as Sun can produce servers that offer roughly the same price/performance ratio as Intel (or AMD), then Sun will continue to be the vendor of choice. That was ultimately what sunk the mainframe world, well except for one notable vendor (IBM), that a small captive market didn't produce enough revenue to support the R&D needed to keep pace. The incremental cost to produce a chip is small. The R&D to develop that chip is enormous. As you say, time will tell.