I've created a plugin and added it to WP plugins repository.
Later, I've seen few mistakes on readme.txt
file. So I've fixed it and commited the changes:
svn add --force trunk/readme.txt
svn ci -m 'Fix readme.txt'
Then, the changes have been reflected on WP plugin page.
I've done a few more changes on the same file and commited them again, but the last change is not updated on the WP plugin page.
As you can see here, the SVN repository has the last update, but it is not reflected on WP plugin page (look at "Description").
Here is shown the last update ("Fix 4 readme.txt").
As it is my first WP plugin, I'm not sure if I just have to wait some more, or there is something wrong on my last update.