It worked for me with 500 posts per page on BoB's simplified style, but not on any of the others. The relevant section of functions.php deals with replacing all of the variables in the style templates with actual code, so something strange is going on there. I wouldn't expect it to have used up 32MB of RAM on the server just to render 250-odd posts, so maybe there's something wrong with the templates. The other solution is to bump up the memory limit for PHP, but that's not ideal. Either way, it's a job for Warren and Michael (or maybe Samuraid if it's the templates).