The ending certainly piques one's interest (as it's supposed to), but the rest is pretty average.
The Lurker's Guide has a summary here.
Admittedly, my eyes glaze over during large-scale battle scenes. 'Tis significant indeed that this episode features the first all-out, no-holds-barred fight against the Shadows, but during the scenes in question, I tune out only because I always have trouble following events. To me, it is the aftermath of a battle that's far more interesting -- and here, unfortunately, JMS kind of skimps on providing us with said aftermath. That's somewhat understandable, as JMS is more focused on building a bridge to next week's slam-dunk feature episode, but when you compare this episode's battle sequence to, say, the battle sequence in Severed Dreams, you definitely feel the absence of the human dimension in the former.
JMS also ruins our fun a bit with his exposition. One of the reasons Lady Morella's prophecy fires a fan's imagination is that it is never explained; we the viewers are left to interpret that prophecy for ourselves. In this episode, however, JMS spends a full scene laying out the meaning of Sheridan's Kosh-induced dream for us, and I think that's highly unnecessary. Of course Sheridan's "equal and opposite" is his wife. You don't need to spell it out for us in large block letters.
On the other hand, it definitely pleases me that Franklin finally "meets himself" and realizes he's been a self-indulgent, whiny bitch all this time. As Franklin himself remarks at the end, he really did need a good stiff kick to the head. And the appearance of Anna Sheridan in the very last scene of the episode is the sort of OMGWTFBBQDeadWomanWalking! cliff-hanger that expertly launches us into the events of Z'ha'dum.
As I said in my summary comment: nice ending, but the rest is rather meh.
The performances are decent all around. Rick Biggs in particular does a nice job with his character's revelatory moment.
There are no strong messages to be found in this episode, but it was nice to see Franklin abandon his dive into his own navel.