While BlackBerry 10 smartphones have been delayed until the first quarter of 2013, the platform will still advent this year on the BlackBerry PlayBook, according to a leaked development roadmap published by BlackBerryOS.com. The roadmap shows that the 4G LTE BlackBerry PlayBook, codenamed the “Winchester 2”, will be released in the fourth quarter of this year, ushering in a brand new BB10 device.

That operating system will also come to the existing BlackBerry PlayBook tablet via a software update sometime in early 2013, as the Canadian manufacturer has repeatedly claimed over the past year. BlackBerry 10 is a close cousin of the PlayBook’s QNX-based operating system, meaning PlayBook apps, such as Angry Birds and Pacemaker, should run flawlessly on BlackBerry 10 tablets and smartphones alike with few or no modifications whatsoever.

The roadmap also shows a device codenamed “Blackforest”, the long-rumoured 10-inch variation on the PlayBook tablet, which will presumably run BlackBerry 10 and appears to be slated for launch in the third quarter of next year. Whether this will be a Wi-Fi only model or whether it will have support for 4G LTE as does its 7-inch predecessor remains to be seen. There’s also an undescribed product called “Naples” advertised on the roadmap. RIM haven’t commented on the alleged leak.