There is already a “trial” edition of World of Warcraft that lets you play up to level 20, but in the latest patch notes, a possible “Veteran” edition has been revealed. The Veteran edition has a level cap, money cap, and chat channel restrictions, but since the only information we have is from patch notes, these things could all change.
What does this mean? It could possibly just be an idea that Blizzard is playing with that will never happen. Likely the fact that it is called “Veteran” edition would lead us to believe that this will allow players with lapsed accounts to come back and play for free.