While many perceive wired networks to be more secure than wireless, the reality is quite different. Unless you have a "Tempest" shielded environment (and you don't unless you work for the Government - at least in the US), data traveling over Ethernet cables is just a readable with the right equipment as wireless data. At least a WEP/WPA protected wireless string forces you to do a little work to get to the data.
All that said, there is a lot going for the average home user and wireless over wired that has nothing to do with the "buzz." The single biggest advantage is the ability to work anywhere in the house without having to prewire it for connectivity. Unlike most office spaces, where either the cubicle or ceiling/wall space has been prepared for cable being run, most house infrastructure is NOT suited to having new cables installed after the drywall is put up without a GREAT deal of time, expense AND expertise. This allows the sharing of infrastructure (notably the ISP connection and the printers) among all the household users with little additional effort.
If you are worried about the security of your data, then take the basic precautions - make sure your banking (and other sensitive) information is NOT on a machine connected to the system, or utilize encryption software (either built into the OS or add-ons - I see PGP announced a new encryption engine for hard drives today (9 May)) or utilize a more secure method of encryption within your network (IPSec is one solution but there are others).
Yes, general wireless networking has, like early networking technologies, a lot of hype and hysteria wrapped around it. Yes, a lot of "experts" are telling you how it should be done and yes, most are flat out wrong (including the tech support provided by the vendors of these products). That being said, O'Reilly and other have released VERY good books on wireless networking and wireless security as well as the steps, both simple and complex, that can be take from average user through corporate infrastructure design. If you want to go beyond that there are even more books and resources on general network security that you can look through to better reinforce the system you are building. Most of this "industrial" levels of security however are beyond what is needed for the average home network.
Like all security issues, it comes back to level of risk you are willing to accept and the amount of work (in terms of resources, time and money) you want to invest in securing that risk. The steps presented here are at the very bottom of the scale in terms of level of effort and level of protection, but for most folks, it is more than they have done - if the 15 wireless networks in my neigbourhood are any indication.