Can I replace 当 with 是 in this sentence Listening to this text, it sounded like 当属 is a word. I can find lots of examples of 当属 acting like a word, but dictionaries don't seem to regard 当属 as a word. 

Could I simply replace 当 with 是 here?

...其中中国人感触最深的当属汽车进入家庭给我们带来的种种便利以及它给中国人的生活带来的改变。
当属 is an abbreviation of 应当属于, which means should be.

应当 means should, 属于 means be/is (of which the original meaning is belong to. Here maybe you can interpret it as attribute to? I'm not sure.)

So you can say 当属 or 应当是.