How infuriating - I had already started writing this article when we had a power-cut - no back ups !
The point of this was that having installed "Flock" under Linux and got the direct blogging and mail working I later discovered that I could NOT view You Tube video content which was rather annoying, as I have a host of other browsers that play video fine - it appears to be a common problem, but the answer is simple.
Fire up a terminal and Navigate to the folder:
usr/lib/firefox/plugin and copy the file 'flashplugin-alternative.so'
Then paste it into your flock/plugin folder wherever that might be on your system (Mines in the home folder) and viola ! It "should" now work with You Tube.
I installed this browser on XP and it worked ok - I like it because it has a built in blogging facility (bit like firefox's scribefire) and you can stay linked to your blog and post from within the browser, you can also pull pics,videos and such right off the web - and you can also set up your e-mail as well - speed wise it's comparable with Firefox or Chrome - I did'nt think I'd want to use it too often as this particular feature did'nt work but now I find I'm using it all the time.
NB: You'll need to "chown" the file flashplugin-alternative.so, as it's a root file and will be locked
Have fun and hope this is useful to someone - Enjoy - Peter G4NKX