1. Alter links to ecommerce sites to forward users to a particular company's URL.
2. Replace affiliate markers on such links with a different affiliate marker.
...and do these things on every link on Livejournal, regardless of context.
I personally like my Dreamwidth+crosspost solution, and have three invitations on hand, but I'm not going to remove all my LJ content. If you are staying on LJ, I will still be paying attention - if you are migrating elsewhere, please let me know so I can find you there.