Hello
I have integrated swfupload based upload to our older site @ http://mihd.net/
(alexa ~1000 http://alexa.com/data/details/traffic_details/mihd.net)
I will see how it works for a few weeks and copes under thousands of daily users before adding it as an alternative upload option to our newer site @ http://ifile.it/
so far getting some people complaining about random i/o error messages from the flash upload but its nice alternative to the pure ajax upload at ifile.it, if this works well ill expand it for multifile select / queue upload, the current one is just single upload to keep it plain and simple 
anyways thanks to the creators of this wonderful resource! i have added credits to you from the javascript source 
March 24, 2009 - 7:55am
update
few months ago mihd.net merged with ifile.it which uses ajax upload, and the whole flash10 debacle was causing issues
but we will be looking into flash again
down road
great project here