For the past few months, emTube (arguably the best YouTube client available for S60) has been rendered useless in streaming YouTube videos. This was likely because of changes on YouTube's end but unfortunately, Sebastian seems to have dissappeared and so no new versions of emTube were created....
However, I've been recently trying to get it to work again by manually editing user agent strings and xml files stored in the system folders but with no luck.
I tried again this morning and to my surprise I was able to load and play videos fine on my N95 8GB, no errors at all!
Is your emTube now working? Reports at HoFo seem to suggest so!