Rebecca Goldstein sees a spike for Spinoza, partially because of "the heightened public interest in the raucous debates between science and religion":
Spinoza’s identification of God with nature […] makes an invaluable contribution to this issue—precisely because it’s subtle. As does his attempt to establish morality on the purely secular grounds of the scientific study of human nature.
From Spinoza’s The Ethics:
[W]hatsoever can be perceived by the infinite intellect as constituting the essence of substance, belongs altogether only to one substance: consequently, substance thinking and substance extended are one and the same substance, comprehended now through one attribute, now through the other. So, also, a mode of extension and the idea of that mode are one and the same thing, though expressed in two ways.
This truth seems to have been dimly recognized by those Jews who maintained that God, God's intellect, and the things understood by God are identical. For instance, a circle existing in nature, and the idea of a circle existing, which is also in God, are one and the same thing, displayed through different attributes. Thus, whether we conceive nature under the attribute of extension, or under the attribute of thought, or under any other attribute, we shall find the same order… Wherefore of things as they are in themselves God is really the cause, inasmuch as he consists of infinite attributes.
The Dish 