[Eagle Creek]

The best way is get on that will redirect from old URL of the threads, directly to the new URL of the thread.

That already was the case when I used pointers. When I used abc.com/forum/showthread.php?p=123 it would redirect to def.com/forum/showthread.php?=123. I guess this is one of the most important things otherwise like 90% of my links would be dead.

Unless its 100% necessary to do such a move, I wouldn't recommend it.

Unfortunately it is and gladly we don't have to do things like this on a regular basis. Nevertheless I want to minimize the problems caused by this.

I plan on running a certain query on the post table so all links to the old domain will be replaced by the new domain. Although this will solve the problem internally, I can't change all the sites linking to us (obviously).

So basically what you saying is:
1. Use aliasses.
2. Place a .htaccess in the root of the website that takes care of the forwarding I've read somewhere that editing the httpd.conf is preferable over using a .htaccess, is that true?
3. Wait some time until Google fully crawled the site again.
4. When Google understands we are using the new domain we can use the pointers again.

Right?