GungaDin,
As WBH stated and i said, God does not need to be Christian/Muslim or Jewish...etc...it is universal...Your God could be Elvis or Budda or many gods....or none. or .yourself...
I cherish freedom of religion and separation of Religion and state.....However, this is an oath ...ceremonial event...and legal requirement
Of course, this is a democracy...you can say whichever you want ....
Just keep the following in mind:
The 1st Paragraph Declaration of Independence refers to
GOD
"When, in the course of human events, it becomes necessary for one people to dissolve the political bonds which have connected them with another, and to assume among the powers of the earth, the separate and equal station to which the laws of nature and of nature's
God entitle them, a decent respect to the opinions of mankind requires that they should declare the causes which impel them to the separation."
Also, N-400 application is not complete without ALLEGIANCE FOR CANDIDATES FOR NATURALIZATION which ends with "Help me God".
Accoding to this ruling, it can not be waived, may be they are new developments.
http://www.justice.gov/olc/oathlltr3.htm