I'm not surprised it wasn't viewed by the full court. For one, no matter what they did, it would end up at the Supreme Court anyways. So why bother?
Secondly, the original decision was, legalistical, pretty air-tight, and drew heavily on all the latest Supreme Court decisions on Church/State seperations and schools.
There were only two "outs" to throw out the initial decision. They could decide Newdow lacked standing, which is merely postponing the inevietable because if Newdow lacked it, there are many parents who have standing to contest free and clear, and with a decision already on record, it'd end right back in their lap.
The could go the Supreme Court's general route, and claim it's harmless "ceremonial Deism" (which, personally, I'd think the Christians so up in arms about his decision would find insulting). However, the original decision pretty much tore that claim to shreds too.
I've been looking forward to seeing this case hit the Supreme Court. Should they vote to overturn the decision, their legal reasoning should be very interesting, as they'll be having to write exceptions to decades of heavily established decisions.
It probably won't be a Bush v. Gore "This ruling only applies to this case, and no others" type of ruling, but it'll be quite interesting all the same.
This case, and the Texas sodomy case are going to be quite a delight to watch.