Housing Bubble

Is there a housing/real estate bubble. A search yields 383,000 links. Call me a "consciensious observer" when it comes to this issue. I (we) have our primary estate and a vacation property. Neither of which was ever intended to be a money maker or flip property. But it's interesting to think how much we potentially could have in the bank if we sold the vacation property. We choose not to mostly because if we sold we could not afford to buy anything else as nice. So I worry little about a bubble bursting in terms of my possible personal loss. However, I am concerned for others who may choose to get into a flip property right now. I'm pretty sure I would not do it.