Land Tax is no longer banned.
While the Legacy metagame is healthy, the DCI is still interesting in occasionally unbanning some cards to see if they improve the format. The top tournament decks in Legacy include Reanimator, RUG Delver, and Sneak and Show. Land Tax has been banned since 2004, doesn't seem to directly add to the top decks, and could make the format even more diverse. While there is always some risk in unbanning a powerful card, the DCI thinks this is a reasonable risk to take.
The DCI looked at the results of competitive Standard events. We found that while a high percentage of the participants played WU Delver decks, that the win rate of those decks was very close to par. For instance, in a recent MTGO PTQ, the win rate of WU Delver decks against non-Delver decks was a bit under 51%. In general there are decks that the Delver decks is strong against, and decks that it is weak against, but on average the deck tends to get results close to average. Additionally the number of people playing high level Standard events is the highest ever.
Looking at the Magic 2013 card set, it appears that there may be more tools for other decks than for the UW Delver deck, though time will tell if this bears out. The DCI will continue to observe how this plays out, but is taking no action.