Denise – Thank you for your care and stubbornness etc. Anyway, apologies if this issue was brought up recently on comment threads and I'm merely repeating it.
tl;dr version. For those of you who are considering deleting your LiveJournal once you've done your import, and your LiveJournal contains a lot of video embeds, DON'T DELETE THE LIVEJOURNAL UNTIL YOU'VE CHECKED THAT THE VIDEOS EMBEDDED CORRECTLY ON DREAMWIDTH. (Sorry for shouting; I won't do it again.) Some videos won't show up because e.g. the video is now deleted from YouTube, too bad. But others will be real, available videos that won't embed on Dreamwidth 'cause the original embed code is old or contains Shockwave Flash; sometimes Dreamwidth will indicate this with a blank space or with a message containing the word "Invalid" or "Error," but sometimes Dreamwidth will insert a different, incorrect video from somewhere else on your Dreamwidth. At least, this was my experience.
In any event, for many of these the LiveJournal embed code will be your only way of figuring what it is you originally embedded, and if you delete your LiveJournal you'll have lost this code and won't know which videos to reinsert on your Dreamwidth. You can always delete your LiveJournal later, in a couple of weeks, once you've figured out if this affects you.
Video embeds after the import
tl;dr version. For those of you who are considering deleting your LiveJournal once you've done your import, and your LiveJournal contains a lot of video embeds, DON'T DELETE THE LIVEJOURNAL UNTIL YOU'VE CHECKED THAT THE VIDEOS EMBEDDED CORRECTLY ON DREAMWIDTH. (Sorry for shouting; I won't do it again.) Some videos won't show up because e.g. the video is now deleted from YouTube, too bad. But others will be real, available videos that won't embed on Dreamwidth 'cause the original embed code is old or contains Shockwave Flash; sometimes Dreamwidth will indicate this with a blank space or with a message containing the word "Invalid" or "Error," but sometimes Dreamwidth will insert a different, incorrect video from somewhere else on your Dreamwidth. At least, this was my experience.
In any event, for many of these the LiveJournal embed code will be your only way of figuring what it is you originally embedded, and if you delete your LiveJournal you'll have lost this code and won't know which videos to reinsert on your Dreamwidth. You can always delete your LiveJournal later, in a couple of weeks, once you've figured out if this affects you.