Om Malik’s GigaOm has raised another round of financing – $4.5 million – bringing the total amount the blog network has raised to $5.3 million. This round was led by Alloy Ventures. Previous investor True Ventures joined the round as well.

GigaOm, one of the first blog networks to raise money, has joined b5Media, Silicon Alley Insider, VentureBeat and Paid Content (acquired), among others, in raising capital. Holdout ReadWriteWeb is said to be testing the waters and looking for a round of funding as well. This is something I’ve recommended against, and we are one of the last large blog networks to remain independent.

Still, I can’t blame Om’s reasons for raising the round – aggressive expansion, software development and a nest egg for troubled financial times ahead. Congrats to him and his team, particularly newly promoted CEO Paul Walborsky.