What do you think?

Thanks guys. :)

Depends on who this him/her is. No matter who it is though, be it an aquaintance, friend, or more, its rude to not say goodbye.

Well...I've gotta say I agree with Bob. Yes some people think its very rude but there are a lot of people that just don't say "goodbye". I personally refuse to say "goodbye" unless I mean just that, not in until I see them again but as in "This is the last time I'm going to see you and never want to see you again" type thing. So really it all depends on the person and how they view the word. I hate it when my fiance says goodbye to me when he leaves or hangsup the phone, makes me feel like he's actually saying Goodbye goodbye

No because "goodbye" is just a word & sometimes words are not needed. From the looks, not the lips, is love reflected.

I don't like "goodbyes" but prefer alternatives like "Goodnight.", "See you in the morning.", etc. It sounds more inviting, like you want to see them again.

Hehe, this is why i always say see you later or speak soon, lol. avoids all confusion.

"edit again: i didn't meant leave without saying goodbye. i meant leave a conversation midway, without notice, or any word as to the fact that they are cutting the conversation, or anything."

^ Really? That's hard to determine from your question.

I don't say goodbye cos goodbye to me means forever....
i don't think it's rude it's just the way the person is...i have many friend who don't say bye or cya but i don't find them rude or disrespectful, it's just who they are....

Say Goodbye. You may never talk to that person again. Anything could happen.