[steven]

I'm glad to see this thread heading in the right direction. I couldn't figure out what "go" and "ga" had to do with one another (I thought for a second that "go" was like "go"han's "go", like MMM, too.

At any rate, I think that が and を are similar in their usage. The problem with most of the examples so far is that the were dealing with adjectives.

ie: 私は犬が好きです

While that translates into "I like dogs", don't let English's "like" verb deceive you... 好き is not a verb, but an adjective. That is a problem I have noticed with textbooks and teachers who teach Japanese to English speakers. That will usually be one of the first, if not the first grammar point. While I think there are cases where you can use を with adjectives like that, you'd be dancing close the the fire if I'm not mistaken.

ex) 私はそばを好きです。
This sounds kind of weird and incomplete when compared with 私はそばが好きです。

If, however, you were to elaborate a bit and say:

ex) 私はそばを死ぬほど好きです。

Then I think it would work. Otherwise you might be eating "dead soba". But the dead-ness is what's appealing to you.
Usually, though, I think it's a better idea to use が with adjectives like that.

I think it's also safe to say that が puts a bit more emphasis on things.
コーヒーを飲みたい。--> I want to drink coffee.
コーヒーが飲みたい。--> I want to drink coffee. (no exceptions)

I'll try to elaborate more in another post if I have time.