Marvel held its second quarter earnings calls this morning (transcript here), and while you’d expect a good result following IRON MAN and INCREDIBLE HULK, instead the stock has tumbled 3 percent today. The culprit? Profits that didn’t live up to expectations on the street:

The comics company earned $46.7 million, or 59 cents per share, in the three months ended June 30, compared with $29.1 million, or 34 cents per share, in the same period last year.

Sales were $156.9 million, up 55 percent from a year ago.

Analysts expected earnings per share of 45 cents on revenue of $131 million, according to Thomson Financial.

Marvel shares fell $1.51, or 4.3 percent, to $33.75 in opening trade.

The publishing division–which always plays the plain, wallflower sister at these chats, lingering upstairs alone while the movie and licensing divisions enjoy brandy and cigars with the boys — nonetheless usually enjoys a bit of modest growth. However, sales were down 17.5 percent for 2008 thus far, PW reports:

Operating income also declined in the quarter, falling 3.3%, to $11.7 million. The decline was due to rising costs for “talent and paper,” Marvel said as well as digital investments. Marvel is investing $4 million in digital initiatives in the year.

For the first six months of 2008, earnings were off 17.5%, to $21.6 million, while revenue dipped 3.6%, to $58.3 million. For the full year, Marvel expects sales in the publishing group to be between $130 million and $135 million, with operating margins of 37% to 40%. In 2007, the publishing unit had sales of $125.7 million and margins of 42%.

Although the figure is alarming, Marvel may be a victim of its success last year with Stephen King’s DARK TOWER and THE DEATH OF CAPTAIN AMERICA.