The Nokia EOS (now Lumia 1020) was apparently going to be the first smartphone to have both a quad-core processor and 1080p display on Windows Phone, two features that sadly were not added to the flagship phone.
This was in part due to the GDR3 update for Windows Phone 8 still not released by Microsoft. However, Lenovo may be preparing a flagship Windows Phone sometime this year, in line with the GDR3 update.
Lenovo have yet to make a break into the Windows Phone arena, with Nokia, HTC, Huawei and Samsung all battling it out for market share. Right now the main competitor is Nokia, who have a grand share of the Windows Phone.
The Lenovo phone will apparently come with a 4.7-inch display and will be a high-end move by the Chinese electronics manufacturer, we have yet to see a real push into mobile and with Windows Phone hotting up it may be a clever move.
Lenovo already has a tight relationship with Microsoft on the PC side, meaning if the company wanted to get involved on Windows Phone we are sure Redmond would have no complaints.