I didn't think this episode was too bad. I LOVE the '40s era so for that reason alone, I really enjoyed it. The clothes, the music (especially Joy), the setting - gosh, I loved it!
Now storyline wise, I pretty much liked everything except the Lucas/Peyton/Brooke stuff. I didn't feel that truly chemistry from any of them that truly represented the '40s. That's just me, though. Honestly, I found Joy to be so captivating - she was the only one who I thought truly captured that whole '40s essence.
As far as the episode being cheesy and feeling randon - wasn't it kind of supposed to be? I don't know how you can do an episode centering around a different time period like that and have it fit into the present day storylines. Besides, it was just a dream inside Lucas's head. That's why it didn't bother me as much. Was Chad's writing brilliant - no, I didn't think so but I also don't find Mark or the other OTH writers to be brilliant either. Again, that's just me, though. And really, season 6 was overall a boring and over-the-top with cliched cheesiness season (IMO) so at least there was something different and fun to watch.