I too would consider myself a pantheist.
Having studied Philosophy at university, I came across Spinoza's work, but it hasn't been until recently that I've begun to fully appreciate his ideas.
I'd consider myself a 'naturalistic pantheist', as when I look at the world and the universe, I can't help but see everything as being connected in a fundamental unity.
The universe is a supermassive thing, without inherent meaning or purpose. We as human beings are a part of nature (how can we not be?), therefore we are also part of the universe, and as we are conscious self aware beings, this in turn means that we as individuals ARE the universe itself experiencing itself through us.
And if the definition of God is the infinite, the creator, the destroyer etc, then that means that God has to encompass everything, including the universe, and cannot be separate from it (as God is infinite), therefore everything in the universe is God, and we as human beings are simply God becoming aware of himself (through our self aware consciousness).
Therefore pantheism is true