I liked this episode because it showed how tragic Charlies life was and what an interesting character he was. Also how great things used to be when the show was more character based with its great characters moments. Its sad knowing now that the reason why Charlie was on drugs is because his brother was taking and that his brother is off drugs because he sold his piano and ran off on him. Its interesting the drug talk that Jack has with Charlie when in the future he becomes a major drug user.
I love how Michael is able to use his construction expertise to help dig Jack out. I wish they would have used that more besides the season 2 time when he found the Hatches blast doors.There are also some great Sawyer moments in this episode that will lead up to his episode.
Its also interesting to note the futility of Sayid's walkie talkie plan since the Looking Glass was interrupting all radio broadcasts. I wonder if they would have figured out that something was blocking the transmissions if Locke had not knocked out Sayid and destroyed his radio equipment.