Google announced today that they're doing some "winter cleaning" by getting rid of some of their services and features that they think weren't getting a lot of use. One of the biggest services they're getting rid of is Google Sync, which was designed to allow access to GMail, Calendar, and Contacts via the Microsoft Exchange ActiveSync protocol, but the company is recommending that users move to alternatives.
As a replacement, Google is recommending CalDAV for calendar, CardDAV for contacts, and IMAP for email, but iPhone owners will also likely use the new Gmail app for email anyway. The company says that Google Sync will no longer be available on new accounts beginning January 30, 2013, but it will still work for users who already have it set up.
Google Sync will also be fully supported for people who have paid for a Google Apps account for business, government, or education purposes. Of course, this shouldn't affect a lot users, since most mobile operating systems, including iOS, support CardDAV and CalDAV, but it'll definitely take some getting used to as far setting up Google Sync differently than before.
Also as a part of the company's winter cleaning, Google discontinued some of their "less popular" Calendar features, such as appointment slots and Smart Rescheduler. They're also shutting down their Issue Tracker API in Google Code, and will also be discontinuing their Punchd Android and iOS app, which was an app that could store loyalty cards from various stores.