I’m having the same problem and removing pingomatic from the ping list didn’t help. When I try to post a new entry, WordPress just hangs for like a minute before prompting me to download post.php as others have described. I don’t know if this is related, but my Dashboard usually takes 2mins+ to load.
I’m running 2.0.1, which I upgraded to last night after doing a clean install and DB restore. I was having this problem before on 1.5.2 and had hoped the clean install would fix it. No such luck ?? I’m wondering if its a server/host problem as I setup a WordPress blog for my sister on the same hosting account and she experiences a similar problem.
Thanks!