The Finnish daily Taloussanomat is reporting [link in Finnish, if you can translate please do so in the comments] today that Nokia will use iTunes to power the N91 music phone. Scheduled to ship in the fourth quarter, the N91 includes a 4GB hard drive which would put it head to head with Apple's iPod mini. This is the first hint we've heard that Apple will be making a mobile move outside of Motorola.
Motorola is widely speculated to launch its first iTunes handset by the end of September. Due to differing practices between industries (Motorola typically announces products well before they ship while Apple prefers to announce and ship very close to eachother) the official announcement has been set back several times. Motorola's CEO confirmed to press last month that the phone would ship before the end of the current quarter (video).
UPDATE: Nokia is now denying the rumors, but states it may be possible to add iTunes later:
bq. "There is no commercial agreement between Nokia and Apple to integrate iTunes into the N-series devices," said Kari Tuutti, spokesman for Nokia's multimedia division. "But since this is based on a computer platform, anybody -- including Apple if they so wish -- can very easily develop this kind of application and offer it to consumers, via the Internet for example."