Dude -- relax. Regardless of how you feel, Superman is going to get a sequel. This darn TMZ "source" is being blown WAY out of proportion. One piece is all that's been offered -- and BTW, no one else is confirming this $200 million threshold (everyone keeps citing this ONE source), and quite frankly, there are far more bloggers (some of them screenwriters) who are denouncing this talk as complete bulls*%!@ -- and I tend to agree with them.
No matter how you slice or dice it, Supes is a franchise for the WB, and the WB ain't about to let go of its star because of ONE sour opening. To do so would be a MAJOR blow to the company. It's like Microsoft coming out and saying, 'sorry, our Windows OS was disappointing -- so we'll stop releasing new versions now.' Many equate the WB with Batman and Superman, so don't think for a second that executives inside WB won't find a way to bring the sequel to life -- with or without Singer (though frankly, I'm sure it'll be with Singer).
Whatever you want to say, Supes will gross awfully close to $200MM by the end of its run. And remember, even though Pirates and X3 did well, they are the exceptions rather than the rule this year.
Others, from Cars to Posiden to Da Vinci to MI3 haven't fared well at all. In fact, despite what everyone keeps calling SR, Superman will prob. be among the top 10 earners this year anyways.
Until we hear anything officially from WB, don't hold your breath on betting Supes won't get his sequel. The WB will make at least one more, and I suspect it'll be even more closely monitored and talked about than this one.
Now that's scary.