The recent rules updates was the first sign of changes: http://www.games-workshop.com/gws/content/article.jsp?catId=cat440134a&pageMode=multi&categoryId=1000018§ion=&pIndex=1&aId=3400019&start=2
Here we see that Dark Angels and Black Templar's finally get the toys that the Space Marines, Space Wolves and Blood Angels have already been enjoying. 3+ storm shields, apothecaries that give Feel No Pain to their unit and so on. This has sparked a new interest again to these armies to some small degree.
What is this? A new thing for the Eldar? Looks like GW is again trying to draw some interest to the older lines with an overturn of their own edict of no updates or adding to a codex until it is updated. What is funny is this is ANOTHER heavy choice which is prime for an Eldar army and had many good choices to choose from. I doubt you will see this appear much on the tables for tournaments. Perhaps more for fun games and Apocalypse games.