Well, usually it means "I'm bored of you, and I want to get the hell out of here". However, it has to be judged in context, because there is a lot more to communication than words.
A couple of weeks ago, I was chatting up this girl and it was going fairly well, when I got that line. The difference is that I already got her number earlier that night, and was bumping into her the 2nd time as we discovered a mutual friend. In hindsight, I think I was coming on a little too strong for her at that point and she's a shy girl, so she had to get away. Her vibe was definitely that of an interested chick. I just said "OK, catch you later"
. Two minutes later, I walked past her standing by herself with a drink, and dropped by & whispered in her ears "Hey there, I think your friends are ignoring you!", winked and continued on my way. She blushed. A week later we went on a first date which went pretty well and we have a 2nd in 2 days.
