Do you remember the slogan Java Everywhere – write once, run anywhere – WORA, sometimes WORE or by some, and here I mean .NET developers (like me), called Just-W*ORE. This slogan saying you can write Java code on any machine, compile it and run on any device, was very popular a couple of years ago. Is it true, though? Could HTML5 be such a technology to fill this hole? We will present you another point of view about the HTML5 empire than presented by Kamil in his last blog post. Here I will try to present some of the advantages and disadvantages of HTML5.