Spinner.com recently featured a list of "Two-Hit Wonders," musical artists who have had two songs in the US Top 40. The title and the tone of the article implies that these are just people who are one song better than the usual flash in the pan.
Which is a great disservice to artists like Crowded House and Whitesnake, who, while having technically only two hits, still have had long careers and a large fanbase. Not hitting the Top 40 doesn't mean not hitting at all. There are specialized charts tracking music that caters to more specific tastes.
Suzanne Vega has been featured and reacts in the NYTimes. Interesting piece, especially the part discussing the songwriting process for "Luka."