FLV? (Yeah I know, but ...)

I'm developing for a website where there's currently 3 video formats
for every video: Real, Quicktime, and Windows Media Player/ WMV.
(Quicktime to support Mac, WMV for Windows, Real for I don't know what.)
The overhead of producting all these versions should be reduced, and
we're now pondering FLV -- Movies in Flash 6+.

Now, my questions, and I'd greatly appreciate any help:
1. Is FLV "good"? (Good user-base, reliable future, good quality)
2. What could be another alternative to support a large userbase with
the minimum possible video formats? (E.g. I almost think Realplayer
support doesn't add much support for systems, but I could be wrong.)
3. Any other comments...?

We will check quality and download-time of FLV ourselves of course but
I kind of want to get a "feeling" for this format, since I don't find
much coverage of it online. In the meantime, we might set-up a system
to track how many people on our website support Flash 6+.
Thanks!