To use the 'I' prefix for interfaces or not to

Question

That is the question? So how big a sin is it not to use this convention when developing a c# project? This convention is widely used in the .NET class library. However, I am not

Answer 1

Ask yourself: If my IDE could give me some hint in the text (e.g different colour, underline, italic...) that the type was an interface would I still bother?

Sounds like you are naming the types like that just so you can tell from the name something about parts of the definition other than the name.