Several others are using these two chips.
ARM926EJ-S
Toshiba, Fujitsu,Texas Inst.,Sun Micro,Kawasaki,Kyoto,STM Micro,Samsung,
ARM1026EJ-S
Toshiba, Fujitsu, LSI Logic, Samsung
There are other companies too. These are just some I wrote down. Arm's list includes companies who may have software that integrates with their chips also. Microsoft is on the list for both of these chips. I don't know if Microsoft mfgs. products other than software.