The Phillies pulled Cole Hamels from revocable waivers, and the left-hander won't be traded to the Cubs, as the time within which the two clubs needed to complete a deal has expired, per Jon Heyman of CBSSports.com.
Hamels was placed on waivers -- which is standard procedure in August, to remove hypotheticals -- a few days ago and reports surfaced that the Cubs had placed a claim on him. From there, the options were that the Phillies could just let the Cubs have him (in which case the full remaining salary would all go to the Cubs, which is substantial), pull him back and keep him or work out a trade. In the latter case, the Cubs would have had to get any players on the 40-man roster through waivers.
In choosing to pull Hamels back, the Phillies now won't be able to trade him until the offseason unless they get him through irrevocable waivers. If they try to do that, it seems pretty likely the Cubs would claim him again and take him without having to cough up any prospects. So expect to hear nothing more about Hamels moving this season.
It bears repeating that the most important item regarding this subject is the Cubs' willingness to spend big on pitching. With Jon Lester, Max Scherzer, James Shields and more on the free agent market this coming offseason and a pretty low Cubs payroll for 2015 as things stand, expect them to be a major player.