Just a little disclaimer here as I've recommended GLD several times in the past.
I still think gold is a necessity for any portfolio, but I'm no longer comfortable with ETFs (GLD, IAU) as a vehicle for gold exposure. I've alluded to this before, and now more and more evidence is coming out that the ETFs don't really have all that gold in the vault and they likely are involved with gold leasing and derivatives, exposing them to counterparty risk from the dirty banksters and hedge funds. They are simply not transparent. It's becoming increasingly apparent that there is a lot more derivative paper gold out there than real gold in vaults. ZeroHedge has been covering this well, and here is the most recent post that explains it well. This was once conspiracy theory stuff for gold kooks, but it's becoming more credible and now even capturing the attention of mainstream blogs like the Huffington Post.
If you can get out of GLD without paying murderous capital gains taxes, I'd recommend switching to physical gold.