The TCC5 does the required 2-2-2 timings for the Rev 2 and much of the TCCD won't. The higher rated memory, such as the PC4200 and PC4800 Platinum will most likely be TCCD, but if it does what it's supposed to it shouldn't make any difference.
Update: I have been told that most of what is shipping now is TCC5. The stuff kicks A**, so there are no worries.
everyone knows that TCCD has been discontinued. don't worry, samsung's other chip is going to be considered as a replacement. their TCC5 chips are showing up in many sticks. i've heard that ocz uses it in their platinum pc3200 rev2. now i get an rma back from OCZ on the pc3700 platinum and it too has tcc5. i'll post some results and show whether it's good or not.
OCZ Platinum Edition Revision 2 chips, labeled v1.1, are now using Samsung's replacement for TCCD, TCC5. Little is known about the TCC5 chips now, OCZ sources claim the chips do latency 2-2-2 more effectively than the TCCD chips, and others using this memory have claimed it to be of a lesser quality than TCCD and have been hitting walls at 260MHz.
A real concrete analysis of these chips is not availible right now, OCZ claims they've sent out testing modules to numerous review sites and we'll see the results shortly. I have a set with the TCC5s in my possesion now and will post some results here shortly once I get my system configured and optimized.
The general public seem to agree that the TCC5s like more vDIMM than the TCCDs though, and OCZ has reassured customers than the despite the labeled "2.9v warranty void", you can pump up the voltage as much as you like and a hassle free RMA will be offered should the worst happen.
Many explain the recent price of drop of the Rev2s is because of the use of TCC5 chips, and until we get a bit of info on these chips, I suggest you refrain from buying Rev2s, or even other memory labelled TCCD, as it may infact be TCC5, which may be of a lesser quality than TCCD. The again, it may be heaps and bounds better, just wanted to inform you guys.
For a list of memory using specific chips (although it may not be accurate as it still lists the Rev2s as TCCD), look here