(alternatively Don't say I didn't warn you, or I've been expecting you, Mr Bond)
Here's where I allow myself a smug moment - this mechanism has always seemed to me like a loophole that would be closed at some point time, so I've been a constant advocate of not using it. Whenever a customer has asked for this, I've asked them to confirm in writing they are happy for us to expend time and effort (and therefore their money) building something that may break at any time in the future and that we may not be able to fix, ever. Unsurprisingly there has been no takeup of this.
Now I realise that this post is painting a picture of doom and gloom, but I don’t think its all bad news. Given that the hacks will continue to work until the Summer '15 release suggests to me that there’s something to at least particually replace them coming in a future release. Knowing Salesforce as I do, I’d expect it to allow enhancements/additions to the standard page without the total hijacking that is currently possible.