I am having the same problem with WP 3. Although I cannot access the FTP logs, I do experience the slowness when performing FTP related functions like installing plugins or themes. Sometimes the whole process fails altogether. The page will also time out.
To monitor the installation I will go into the wp-content/upgrade/xxx.tmp/xxx/ folder and constantly refresh to see the files ‘disappearing’ as they are moved into place. The time it takes to finish the installation is rather proportionate to the size of the files, and the number of files to be moved, but the files are usually too small to even matter.
WP 2.9.2 was fine.
