Fox

Tuesday night's "Battle of the Davids" on "American Idol" should be a humdinger. (To repeat a word used last week by judge Simon Cowell.)

Yes, it's the Season 7 finale, with the contestants singing for viewers' votes for the, whew!, last time. (The show is at 8 p.m. on Fox40.)

And hey, I predicted it would come down to the two Davids back when the judges picked the Top 24. Well, I had a hunch.

Question is, who will appeal to a larger fan base? David Archuleta, 17, definitely has the tweener vote and a good chunk of what Simon calls the "granny" vote. David Cook, 25, is tight with the 20somethings, but I think his strong suit definitely is with rockers and women in their 40s and 50s. (That would include me. No bias, just an opinion.) To me, David C. is certainly more versatile and, perhaps, more marketable.

Meanwhile, it will be interesting to see which song won the songwriting contest. Last season's "This Is My Now" was, well, not one my favorites - mostly because the title would never be something anyone would actually say, let alone sing. So I'm hoping for a song that will challenge both finalists' creativity.

But, what "Idol" honchos will really be thinking about is the future. This season saw viewership drop by as much as 10 percent for some episodes. The Nielsen numbers have been hovering around 22 million or so for each show - a far cry from numbers in past seasons that topped 35 million!

Of course, the show still leads in the ratings each week. It will likely come down to either tweaking parts of the show next year (read: changes you won't notice), or overhauling chunks of it (not showing the auditions, changing judges).

In the meantime, there are two Davids with butterflies in their stomachs, one interfering stage father (Jeff Archuleta) and a gaggle of girls ready to scream.