Filed this as support, since I'm not 100% sure. If someone else can confirm, then switch it over to "bug".
The GA documentation doesn't mention a couple things with regards to a transactions item's price.
From a small amount of research, it's mentioned that an items price should be the price of a single quantity of an item, with out tax or shipping. This would make sense to me, as this would be the revenue the store gets at the end.
From:
http://productforums.google.com/d/msg/analytics/yNbKKbIc6fQ/FCJH5Rd8074J
Regarding my question to Noel above, about the Price argument in the _addItem() function: this amount, multiplied by each product's quantity, is added up and displayed as "Product Revenue" under "Ecommerce > Product Performance > Product Overview". The Price argument is a product's unit-price, and it should *not* include tax nor shipping.
In this module, I do believe it adds tax to this item, perhaps incorrectly.
$item = array(
'order_id' => $order->order_id->value(),
'sku' => $line_item->type->value(),
'name' => $line_item->line_item_label->value(),
'category' => $category,
'price' => commerce_currency_amount_to_decimal($line_item->commerce_unit_price->amount->value(), $line_item->commerce_unit_price->currency_code->value()),
'quantity' => (int) $line_item->quantity->value(),
);