I'm thinking about asking for the ability to search the member directory by similiarity, and ability to sort my reminder list by "posted" vs not posted. 

Some of our computer types here might know if these things are doable. Don't want to make a pest of myself with our gurus or have them rolling in the floor laughing :)

Any other features  some of you might like to ask for but not sure about?

Ummm... my reminder list already does that.  Seems to default that way.

The Similarity Index isnt searchable yet, but they have said they have that in mind for the future. Since it is based on Genre preferences and members rating books, they are waiting a bit for members to rate more books. It is fairly new that members have to rate a book to add it to your Books I've Read list. Once more members rate more books, they have said they would like to have it become a way to search.

The Reminder list will put all the not-posted books at the end.  You might be able to reverse that into having it put them all at the top.

Here's a link you could add to your browser's favorite list; it will bring the posted books to the top of your RL:  http://www.paperbackswap.com/members/my_lists/reminder_list.php?sby=avail&oby=

Not sure why your link worked, Karen, but it did!