Deleted 600mb Partition on Bootcamp-ed MBP while logged into Windows 8 using Disk Manager. No longer boots into OS X
Presumably you deleted the recovery partition, which is about that size. Boot into Internet Recovery, start the terminal and type diskutil list. If the OS X partition is still there, you should see it as formatted with CoreStorage (OS X doesn't require the recovery partition for a normal HFS+ formatted partition). If it exists, then the solution is to do a reinstall of the OS. This will not erase anything, but it will recreate the recovery partition. Note that you'll have to unlock your disk first if it's locked by FileVault 2.

Lesson for the future: Windows doesn't know anything about CoreStorage volumes, even with all the BootCamp drivers installed. Do not trust anything you see regarding your disks from within Windows, unless it identifies the disk as a format it knows.