Artscroll's Stone Chumash contains a fascinating bibliography (pp. 1297-1303 in my edition). Although I did not count the sources apart from the first page (37) and another one at random (41), I average that to some 280 sources are cited in the commentary of this work. However, a good deal are the names of individual Talmudic tractates or sages, which means that the number of unique sources are less--I think we can agree that "Babba Kamma" or "Rabbi Akiva" perhaps should be combined under "Talmud Bavli," as it does for the Yerushalmi--so perhaps there are some 250 sources.
Still, the bibliography spans all periods and types of traditional sources: everything from midrashic collections to ge'onic works, from peshat oriented rishonim to kabbalistic rishonim; from homiletical commentaries to philological ones; from the Vilna Gaon to Chassidic rebbes; from modern traditionalist commentaries like Ha-kesav ve Ha-kabbalah and Netziv to R. David Zvi Hoffmann; from 20th century Litvishe roshei yeshivot to freelance 20th century talmidei chachamim. I would not be the first to notice that R. Kook, the Lubavitcher Rebbe, Nehama Leibowitz are absent, but this is unsurprising. R. JB Soloveitchik is included. There's no Benno Jacob and there's no S.R. Driver, but that is to be expected.
What's interesting about the bibliography is that Artscroll chose to write a short bio for each one. These are informative, largely accurate, but sometimes interesting in ways that they probably didn't intend.
For example, from these bios we learn that some (mostly) 20th century rabbis were "leaders," while, by omission, others are not.
- Chazon Ish "was acknowledged as a foremost leader of Jewry"
- Chofetz* Chaim "acknowledged as a foremost leader of Jewry" *an unusual departure from Artscroll's transliteration scheme
- R. Moshe Feinstein "a foremost leader of Jewry"
- R. Yaakov Kamenetzky "a foremost thinker and leader of Jewry"
- R. Aharon Kotler "a foremost leader and proponder of the primacy of Torah"
- Pachad Yitzchak (R. Yitzchak Hutner) "a foremost thinker and leader of Jewry"
- R. JB Soloveitchik "an original Talmudic scholar, thinker and leader"
These leaders are: not Chassidic and never "freelance" talmidei chachamim.
Interestingly enough this designation is left off of 'canonical gedolim,' like R. Eliyahu Dessler and most surprisingly, R. Gedaliah Schorr (although it does note that he was called "the first American-trained gadol").
I left off those who are "leading Torah scholars," as many, like R. Shlomo Kluger are called, or those called leaders with qualifiers, like geographic boundaries, such as the Chasam Sofer "acknowledged leader of Hungarian Jewry," R. Samson Raphael Hirsch "great leader of modern German-Jewish Orthodox," Imrei Emes "foremost leader of Polish Jewry," K'sav Sofer "leader of non-Chassidic Hungarian Orthodoxy in the middle decades of the nineteenth century,"
I think it's important not to read so much into who is not called a leader as to who is. The reason why is because it's pretty much clear that these bios were not written juxtaposed one next to the other (which is partly why its so fascinating--it almost seems like a window into Artscroll's corporate subconscious). Thus, I can not detect a hint of disrespect when R. Gedaliah Schorr is not noted as a leader of Jewry. In fact, there really is no disrespect in any of the bios, including R. Soloveitchik's (it is not a repeat of the Jewish Observer fiasco). To the extent that A. is guilty of omissions by not finding even one comment to cite in the name of R. Kook or the Lubavitcher Rebbe, I would note that the Satmar Rav and R. Shach are also absent--not that I think that R. Kook is going to make it out of Shaar Press. But I digress.
Also of note is that the bibliography cites Alexander Kohut's Aruch Hashalem (see comments in post below) and R. Wolf Heidenheim. Now, I know that there is nothing wrong with R. Wolf Heidenheim, but let's just say that there is a reason why Reform Judaism and Its Pioneers by Emanuel Schreiber (1892) mentions him as a moderate early Reformer of the second stage, of the generation following Mendelssohn. This is not to endorse this book's depiction of him, only to note that qualitatively there is no difference between citing Wolf Heidenheim and Moses Mendelssohn in the sense that certainly the former was not "frummer" than the latter. Both were modern, religious men of the Haskalah, in the positive sense which R. Jacob Emden called Mendelssohn a maskil (see R. Dr. JJ Schachter's PhD dissertation on R. Emden for more info). Except for one thing: only one of these two men became a symbol.