You can put an SSD into a mac fine yea, and it will operate...
Taken from wikipedia, cause it can explain it better than I can....
In computing, a TRIM command allows an operating system to inform a solid-state drive (or "SSD") which data blocks, such as those belonging to a deleted file, are no longer considered in use.
Since an operating system command such as delete generally only means the data blocks are flagged in its file system as "not in use" (and thus available for new writes), the operation does not involve a physical write to the sectors that contain the data. While this often enables undelete tools to recover files from traditional hard disks, despite them being reported as "deleted" by the operating system, bypassing the storage medium also means that it remains unaware that the status of these sectors was changed. Because low-level operation of solid-state drives differs significantly from traditional hard disks (see details below), this approach resulted in unanticipated performance degradation of write operations on SSDs. In response to this, the TRIM command was introduced to allow the OS to explicitly pass the information on to the SSD controller, enabling the SSD to handle overhead that would otherwise impact future write operations on the involved blocks. 
Without TRIM support the write times get exponentially slower, ultimately resulting in a HD slower than 7200rpm, and further.
Currently OS X does not support TRIM, so buying a Mac with an SSD, or upgrading the HD to SSD with intention of acheiving faster read.write speeds, will ultimately be shorted lived.