Warning: Spoilers, of course. 
What spoilers did you encounter before and during seeing Babylon 5? (Either on spoiler sites during the show, or from wherever if you didn't watch it during first run like me.) What theories, right or wrong, did you piece together on this information?
I remember one main thing I expected that was proved wrong as I watched the show. One of the things I knew going in, from listening to friends who got in to it before I did, was that Garibaldi would betray the station crew somehow. I didn't know how, but I also knew/was sure of the fact that the station was destroyed in the end. (I can't recall how I knew the second bit, but I did.) I connected these two bits and decided he would probably end up causing or aiding the station's destruction. (After seeing Babylon Squared, I thought it might happen sometime around the flashforward showing fighting on the station.)
On balance, I don't think this harmed things for me. It was always clear something was up with him from the beginning of S4, so since I had the target wrong, I didn't really have any solid spoiler information.
One solid spoiler I did have, however, came from glancing through some Babylon 5 magazines a friend gave me. I shouldn't have, as I was still waiting for the last season to come out on DVD, but I couldn't resist peaking at some of them before seeing the rest of the show. I read some things about Lennier that basically said he would fall out with, possibly betray, Sheridan and De'lenn. I thought I might have gotten things wrong as the show wound down, but at the end, he did it, and I knew it was coming because of what I'd read.

What spoilers did you encounter before and during seeing Babylon 5? (Either on spoiler sites during the show, or from wherever if you didn't watch it during first run like me.) What theories, right or wrong, did you piece together on this information?
I remember one main thing I expected that was proved wrong as I watched the show. One of the things I knew going in, from listening to friends who got in to it before I did, was that Garibaldi would betray the station crew somehow. I didn't know how, but I also knew/was sure of the fact that the station was destroyed in the end. (I can't recall how I knew the second bit, but I did.) I connected these two bits and decided he would probably end up causing or aiding the station's destruction. (After seeing Babylon Squared, I thought it might happen sometime around the flashforward showing fighting on the station.)
On balance, I don't think this harmed things for me. It was always clear something was up with him from the beginning of S4, so since I had the target wrong, I didn't really have any solid spoiler information.
One solid spoiler I did have, however, came from glancing through some Babylon 5 magazines a friend gave me. I shouldn't have, as I was still waiting for the last season to come out on DVD, but I couldn't resist peaking at some of them before seeing the rest of the show. I read some things about Lennier that basically said he would fall out with, possibly betray, Sheridan and De'lenn. I thought I might have gotten things wrong as the show wound down, but at the end, he did it, and I knew it was coming because of what I'd read.
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