One thing that made Brian suspect Walt was "different" happened shortly before his mother Susan's death. As Brian and Susan were discussing her recently diagnosed illness, Walt was studying a book of Australian native birds, seemingly oblivious to the conversation happening in the room. He wanted Brian to look at the entry for the Australian Bronze ****oo. When Brian ignored him, Walt became angry and insistent, demanding "You're not looking!" Suddenly a
bird slammed into the sliding glass door, killing itself on impact. It was an Australian Bronze ****oo.
Let's not forget The Others kidnapping him for God knows how long and making him take tests, Then Klugh asking Michael all of those questions...
I don't think all of that was for nothing...
I could not agree more Barack. Walt will still have major importance in the show and I believe he will find his way back to the island. Just the fact that he still was having dreams about Locke shows that he still has a connection to the island that he will never be able to break. I highly doubt that we have the last of Walt....there is no way his "specialness" was so hyped up to mean absolutely nothing.
I think they were running radiation test, maybe?
And is also that other that can teleport. She was the wife of the husband who Juliet had an affair with.