I thought it was a great episode. Allison Mack was terrific (and looked great to boot) as we slowly see Chloe losing her memories. Once again, this episode shows the benefit of focusing on less characters. Basically, it shows how good this show is when Lois is not there. SW continues to be awesome as Davis and even Jimmy comes across as likeable. Thought those kids did a very good job as Chloe and Clark.
I thought seeing Clark and Jor-El work together was awesome though Brainiac might be the worst kind of villain to get rid of. Nothing keeps this guy down.
I understand why Clark wanted to free Chloe of the burden of his identity but it is absolutely wrong to take someone's memories without their permission. Chloe flat out told Clark that this gave her life purpose in helping people and Clark took that away from her. It also creates a bunch of other problems...one, doesn't think mean she doesn't remember the identitites of Ollie and the rest of the JLA? She was an important assest to them and Clark took that away. Also...shouldn't Chloe have large gaps in her memory or did Jor-El compensate for that?
I'm withholding final judgment on this though because I'm sure Chloe will regain her memory at some point. It might spell the doom (no pun intended) for the Clark/Chloe relationship because I can't imagine her being happy with Clark's actions.
I have to say, between the more pro-active Clark, the lack of Lana hanging over him, and the Doomsday storyline, Smallville has managed to do a great job putting this season together.