We are well beyond moving to 64bit on a needs-only basis. At this point it's about dropping legacy and future proofing. There's also no reason 64bit apps should

We are well beyond moving to 64bit on a needs-only basis. At this point it's about dropping legacy and future proofing. There's also no reason 64bit apps should have a larger memory footprint; the ISA and addressing modes are actually much tidier.