Good episode. It's sometimes difficult to judge the first episode of a "real" two-parter, because the first part is bringing all the members of the story together and building things up. But overall it was done well, and I anxiously await for part two! Here are some thoughts:
Todd and Michael in the same episode - nice. Seeing Major Lorne in action was nice, too.
Michael - for just one person/wraith, he has really done a lot and has become a big pain in the mitka for everyone. First the wraith bug monsters and now poisoning the well, and also what has he done to the Athosians? He makes a good villain.
Who really is the father of Teyla's child?
The poor fetus/baby will be listening to McKay's recordings!
Sam's a scientist, so she can't believe what Teyla says about her visions? They've seen visions of the future, telepathy, and alternate realities, not to mention time travel, body switching, and resurrection, among other things.
Carson - woohoo!!
Looking forward to the next episode!