I've just posted this in reply to
sheenaghpugh 's post at
fanthropology
Rather than a single monolithic central archive, I'm not sure that, right now, what need isn't a really good central directory with links, site descriptions and caveats where applicable.
Whilst I'm no expert, it seems to me that this would fit well with the ethos of the fanfiction community (communities?), could be set up fairly quickly and would provide a more flexible and democratic approach to access.
That said, personally, I think it might be useful if the site were to host a small number of fics, these being chosen for excellence and accessibility, suggested and voted for in the usual manner.
It is, of course, quite possible that this could develop organically into the sort of archive many fans would like to see, in which case the directory format would prove an effective intermediate measure.