From personal experience in Taiwan, I found it
enormously helpful to be able
to meet other Wikimedians from so many different
places. (Japan, Taiwan,
Australia, India, the Middle East, Europe, Canada, the U.S., and many other
places) As well, there are positive benefits of cultural exchange, and
outreach to Egypt and other nearby countries also has positive benefits.
There will always be a certain percentage of attendees that are from the
local country or region, who otherwise will not attend. As mentioned
already, for whatever reasons, the Arabic Wikipedia is still small (compared
to the number of speakers of the language). This is an excellent
opportunity to outreach to them and grow the community.
Then in 2009, we will have Wikimania in another place (maybe Atlanta or
Toronto?), which will draw different people from the local region. Though,
I'm sure there will be people from Taiwan and Egypt who will continue to
come to Wikimania, regardless of where it is. In my experience of
organizing conferences, I find this to be the case.