Despite its pervasiveness, a professional designer would rarely—at least for the moment—specify Arial. To professional designers, Arial is looked down on as a not-very-faithful imitation of a typeface that is no longer fashionable [i.e., Helvetica]. It has what you might call a "low-end stigma." The few cases that I have heard of where a designer has intentionally used Arial were because the client insisted on it. Why? The client wanted to be able to produce materials in-house that matched their corporate look and they already had Arial, because it's included with Windows. True to its heritage, Arial gets chosen because it's cheap, not because it's a great typeface.
From Adobe's Type Topics, a consideration of the ampersand in all its variety:
Ampersand usage varies from language to language. In English and French text, the ampersand may be substituted for the words and and et, and both versions may be used in the same text. The German rule is to use the ampersand within formal or corporate titles made up of two separate names; according to present German composition rules, the ampersand may not be used in running text.
Did you know that the Poetica typeface family (created by an Adobe designer) contains 58 different ampersand characters? I didn't.
It turns out that's not all I didn't know about type. The Rather Difficult Font Game lives up to its name; I scored a humbling 22 out of 34. And to think I used to draw a paycheck as a typesetter. (Hat tip: Dynamist.)
"Down with Arial" handbill graphic from Fawny.org.