Is alignment to erase block size needed for modern SSD's?

From OCZ's "The ABC Guide" to SSD's regarding alignment:

Default Vista and Win 7 create aligned partitions at an offset of 1024KiB.

[...]

Mac OSX Disk Utility aligns partitions in HFS+. As do most newer distros of GNU/Linux.

However, as you mentioned, the Vertex 3 has an erase block size of 2MB, which is not a factor of the current alignment offset; for this reason, I would indeed recommend moving the alignment to 2MB. From the OCZ forums, here's a guide on how to use gparted to align a SSD. There is also this tool for Linux to manually align a solid state drive.

Your data is stored on a SSD with a level of indirection at the block level. Each block can end up pretty much anywhere physically. Besides wear leveling some controllers compress blocks and point blocks with the same content to the same physical storage location.

The erase block size matters more in the effects it has on wear leveling, how much data might need to be copied elsewhere to free all blocks with content in the erase block before it's wiped (otherwise the SSD might eventually end up with only 1 block used per erase block) can also impact performance.