> Well, actually, just one - the endpoint software could just be changed That's exactly what makes your entire argument silly: when you use a piece of software

> Well, actually, just one - the endpoint software could just be changed That's exactly what makes your entire argument silly: when you use a piece of software, you're trusting this piece of software, and there's no way around this, being web-based doesn't change a damn thing compared to any other software with automatic update.