This is one (big) reason why i probably wont be making any more java games (except maybe 4k .
About a year ago I made a puzzle game java applet (http://spacetaken.net/laz3r/). It is a pretty simple game and has little in the way of polish.
Very recently I have been learning flash, using the free flex2 sdk to write flash applets in pure actionscript 3. I converted my laz3r game into flash, added (very little) extra polish, and submitted it to kongregate as something of an experiment - http://www.kongregate.com/games/gareth0/faze.
Right now - in less than 48 hours since upping it - the flash version has had 9326 plays, which is an order of magnitude greater than the applet version has ever had, and I have got a few dollars of ad revenue to boot. Which is just great, basically.
EDIT: I guess the point is that it is far easier for me to get feedback (and people playing my games, which is good by itself) using flash.