I don't see the N64 troubling the SNES or the PS2. Would have a shot at the PS1 though. People are underestimating the respect the PS2 has.
Historical ownership rates as of last check:
PS2: 84.44% (http://www.gamefaqs.com/poll/index.html?poll=4296)
GBA: 81.96% (http://www.gamefaqs.com/poll/index.html?poll=4283)
DS: 76.69% (http://www.gamefaqs.com/poll/index.html?poll=4386)
PS1: 75.99% (http://www.gamefaqs.com/poll/index.html?poll=4455)
GCN: 74.92% (http://www.gamefaqs.com/poll/index.html?poll=3536)
N64: 73.1% (http://www.gamefaqs.com/poll/index.html?poll=4475)
Wii: 69.03% (http://www.gamefaqs.com/poll/index.html?poll=4581)
SNES: 68.84% (http://www.gamefaqs.com/poll/index.html?poll=4428)
NES: 66.83% (http://www.gamefaqs.com/poll/index.html?poll=3544)
PS3: 63.28% (http://www.gamefaqs.com/poll/index.html?poll=4580)
X360: 58.67% (http://www.gamefaqs.com/poll/index.html?poll=4582)
PSP: 53.23% (http://www.gamefaqs.com/poll/index.html?poll=4387)
Genesis: 47.55% (http://www.gamefaqs.com/poll/index.html?poll=4429)
XBOX: 46.1% (http://www.gamefaqs.com/poll/index.html?poll=3537)
3DS: 33.55% (http://www.gamefaqs.com/poll/index.html?poll=4579)
As for why I don't think the N64 would trouble the SNES:
http://www.gamefaqs.com/poll/index.html?poll=2215
Even with seven years of time passing, that's a massive gap.
Other poll result I found interesting: only 6.35% of the site doesn't own at least one of Wii/PS3/360. (http://www.gamefaqs.com/poll/index.html?poll=4499)
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Who knew the Rivalry Rumble would be so predictable? SuperNiceDog, that's who.