Is it a such hard question that nobody can answer?
Looks like I will answer it myself, so based on info found here: http://forums.anandtech.com/showthread.php?p=32184085, the difference can be known from Voltage value which is defined by 4th digit from the end. 'A' stands for 3.3V and asynchronous type; 'C' stands for 1.8V and synchronous type.
Which is why, Vertex 3's: Intel 29F16B08CCME2 - synchronous type, what is quite possible as synchronous Micron parts can be found in Vertex 3 as well;
ADATA 511S: Intel 29F16B08CAME1 - asynchronous type.
And the last, Intel 510: Intel 29F16B08JAMDD - asynchronous ? Will anybody doubt this? Considering high price of 510 series, adding synchronous flash would have put price further of the current one - can be truthful also.
Now it is clear.