There's a similar hashtag on Twitter, but I have far more words about this.
1. I grew up within walking distance of another now-defunct bookstore chain. Other than the library (which was a walk that was five times longer) and raiding my parents bookshelves, this was my primary source for things bookish. They had a tiny young adult section that leaned heavily on the series (Sweet Valley and the like). They did not have a romance section, romance was spread out into the fiction section, although they did have a small mystery section. So when this new bookstore - a store my mom willingly drove me to - opened up with a huge romance section, you can imagine my happiness.
2. As one of those people who used to regularly appear at the bookstore on Tuesdays, I sometimes arrived before the new book got distributed to all the normal places. Sometimes I could find it myself by checking the new release shelves and tables or the endcaps, and sometimes I needed assistance. I have been in bookstores where the staffers (the ones at the info desk even) were not particularly happy to help me look. I never (seriously, never) had that problem at Borders. They didn't always find it, but they were unfailingly polite about the search and in one case, where I told they guy who had checked several sections that I could come back tomorrow, he said, no, other people will want this book to, if you don't mind waiting, I'll do some more checking so we can find it. (I did wait, and he did find it for me.)
3. I like shopping in bookstores where the cashiers were excited about the things I bought, and wanted to tell me that they had enjoyed that CD or that series.
4. Borders ebook section had great search functionality and they always listed clearly the books that were agency priced and couldn't be discounted. (Hint, hint, other ebook sellers.)
5. Borders had an excellent magazine section, regularly carrying titles I had trouble finding in other places. Even other big box or chain stores.
6. Borders had a great craft section offering more than say five books about crafts including knitting, wire jewelry making and beading.
7. I live in an area with a decent number of bookstores, but sadly, without Borders I will lose all but two of the nearest places I can buy romance. At least new. Or in person.