でしょう can usually be understood to mean "probably." But does it sometimes mean the same thing as ですね? What other meanings can it have? Can it mean "you know?"
Aside from the meaning of "probably", I've heard でしょう (だろう) used in the following manners:
In polite speech, でしょうか can replace ですか. でしょうか sounds "softer" and a little less direct:
この色【いろ】はいかがですか。 How about this color?
この色【いろ】はいかがでしょうか。 How about this color? (slightly more polite)
ちょっと分【わ】かりにくいですかね。 Do you suppose it's somewhat hard to follow?
ちょっと分【わ】かりにくいでしょうかね。 Do you suppose it's somewhat hard to follow? (slightly more polite)
でしょう and だろう can be used like ね to form tag questions, primarily when the speaker knows something to be true and is using it to prove a point to or convince the listener of some fact. This use of でしょう often has a rising intonation:
で、帰【かえ】ったときに携帯【けいたい】はかばんに入【はい】ってなかっただろう？ So when you got back, your cell wasn't in your bag, right?
言【い】ったでしょう？明日【あした】、東京【とうきょう】に行【い】くって。 I told you, didn't I? That I'd be going to Tokyo tomorrow.
The question particle か is omitted in this use. In my experience, you're more likely to find だろう being used by men and でしょう by women here, but the split is not well defined, as both are fairly gender-neutral.
There is another slightly different use that takes some getting used to. Weather reporters frequently use でしょう to indicate likely weather:
At first it always seemed like they were asking me for confirmation:)
To agree with previous posters, ですね and でしょう are pretty different. The former is sort of a neutral comment, but can imply a question, whereas the latter is more implicitly asking for some kind of confirmation.
味が変ですね。-This tastes odd (wouldn't you agree?) 味が変でしょう。 - Doesn't this taste odd?
でしょう is like です, but with less certainty. It's used when someone is pretty sure something is that way, but not entirely.
So yes, it's a bit like 'probably', but that's not actually what it means.
It's often used when someone wants to see if someone else agrees with them before committing to it, too.