Question Answered
Thanks!
So, I have gathered the following source from the link provided above.
What is a partition?
A partition is an area of allocated space, a division of the whole overall area of space. In this case our partitions on the Epic 4G are /System, /Data, as well as /Cache. All with set permanent sizes.
What is a partition map?
A partition map is the configuration of our partitions, it's what in a vagueness sets our required sizes for the divisions of our nand also known as flash memory. A partition or partition map should not be confused with a file system. An example would be BML and MTD.
What is a file system?
A file system resides on the partition map and governs the data being read/wrote/moved/etc by the Operating System, in this case Android. Changing a file system is less complex than an overall change in partition mapping. They again, are not the same thing.
What is MTD?
MTD is an Open Source Partition map. It allows those who are using it control over how their partitions are sized and how much space is allocated here and how much space is taken away from there. Currently on MTD we have 689 megabytes of space allocated to our /data partition allowing more to be downloaded from the market as an example. MTD as a partition config has YAFFS2 as a file system residing on it governing how data is transferred and the speed of which it is done. EXT2 through 4 aren't possible on the MTD platform, just as YAFFS2 may not be possible on the BML proprietary platform.
What is BML?
BML like MTD is a partition map, however it is proprietary in nature, Close Source if you will. The size for /System /Data /Cache is set and permanent and makes opening up space more of a task for Developers. Stock the Epic 4G comes on BML, and is running RFS as it's file system, once rooted you can leave RFS for EXT4 (Journaled or Un-Journaled) as long as the kernel you use allows for EXT4. But in the end, changing a file system on BML does not lessen or enhance the control you have over your partitions.
[Source/Credit: AproSamurai]
http://forum.xda-developers.com/showthread.php?t=1387334