Hugh Hewitt has mentioned that there isn't yet a patron saint of blogging. He offered St. Augustine of Hippo as the obvious choice, because of his prolific writing (Confessions, City of God, etc.) He also likes St. Hugh of Lincoln, but that's just vanity.
Personally, after having listened to How the Irish Saved Civilization on tape, I like St. Columba. He was a bard, a miracle worker, and legend has it that he wrote 300 books. He is also the patron saint of bookbinders and poets. Through his and his fellow monks' work at the abbey of Iona in Ireland and beyond, Western Civilization's writings were preserved and spread throughout Europe during the Dark Ages, so that they were still available to help spur and inspire the Renaissance.
Aren't these the descriptions of bloggers? Bards, poets, miracle workers, people whose work has the potential to save civilization.
I give you St. Columba, the patron saint of blogging!