My brain totally farted

and realized (after reading your original thread) you don't currently have the Xenon...right? and you want to access youtube on your Blackberry?
When I had the 8300 Curve, I had the same problem. The only way you would be able to access youtube would be through downloading Adobe Flash. But for some reason, it won't allow you to download it... Now... All of this was said throughout this thread...
If you get the Xenon, your problem will be solved, you will have no problems accessing youtube. This was one of 3 reasons why I switched from Blackberry to Xenon. I originally got the Eternity, liked it, but had problems buffering... so I exchanged it for the Xenon, with other reasons... The Xenon streams the videos very well.
With your current Blackberry, you won't have much of a choice at this point... other than using tinytube I am afraid... At least this was what I found out during my crackberry days. The guys at crackberry.com may have a new solution to get around this... but this is all I have so far...