No, everything that worked before, still does (on 64-bit). A stack segment uses 8kB of virtual address space. It will only use a page (4kB) of physical memory if you don't need that much stack. The operating system will map the second page only when it faults.
If you need more stack, the point is moot because you used more physical memory before as well, it was just split into more stack segments.
I'll refrain from making a smartass comment, just state I understand the difference perfectly. This causes a jump in physical memory usage. See reply to your parent.
If you need more stack, the point is moot because you used more physical memory before as well, it was just split into more stack segments.