A number of the Web2.0 commentators have been discussing the value of creating an account tied to an email address or a nickname.

The majority of those pro claim it reduces the number of things to remember and a number of those against say it reduces flexibility and potentially increases complexity.

I have to say that I agree with the latter view, and for a number of reasons.

I often don't want to give me real email address to a site that I've just encountered and have no "trust" relationship with - so I'll use SneakEmail or similar to establish a presence and see if they abuse my trust. By using a nickname in this context as the identity mechanism it's a lot easier to remember my login, and if I choose later to go back and provide my real email address no-one is affected.

By managing the account based on a nickname the site has a ready made identifier for forums etc. Some people may be less comfortable with that I'll admit but it enables to me maintain a pretty consistent persona across the web without having to think about it too much. LinkedIn and Facebook don't do this particularly well (forcing you to use a real name not your chosen alias. ideally you'd be allowed both), though Myspace, Last.FM, and Del.icio.us  (and others) have better ways to expose your public profile with more control.

Security and protection of my email address. If I'm putting my email address into a form I like to know that the form is secured, especially if it's coupled with a password of any sort. Recently Myspace have been called out for not securing their login script which because it's using email and password could have pretty undesirable consequences. Using a nickname rather than the email address would at least reduce the amount of information shared. Facebook use email address as the log in qualifier but at least their form is secured.

Control over my persona. Some sites allow you to change your nickname which allows you some flexibility over time. Others don't - again there's pros and cons with that, personally I think that flexibility is important as it allows the individual to control their identity in the system. Many forums annoy me because over time as I've adopted a new personality I've no way of going back and re-tagging those entries with something appropriate to re-establish this history (of course some forum users would complain that by changing the nickname I'm re-writing history). All sites need to allow you to change email address to remain current as throw-away accounts expire or you change jobs. Surprisingly even now there are some where changing that is harder than it should be.

Ironically I've recently had to change my LiveID. Although I've had the same account for ten years this month (yes, Hotmail has been around that long. My LiveID started out as my Hotmail login, became my Passport ID and then my LiveID) because it's tied to billing records (for Xbox Live) in Australia I can't use it for premium services such as XBox Live or MSN Direct here in the US. As a result my associated GamerTag will also have to be retired (I wonder if the real reason they stopped calling it Passport was because it made it harder to move countries!)

As Web 2.0 continues to evolve into what-ever Web 3.0 will bring and the implicit web changes the way we interact with sites keeping track of our own identity will become harder. Email addresses vs Nicknames is just one of the challenges, and that challenge in itself encompasses personas, security, trust and ease of use.

Makes me wonder what other challenges we've got to look forward to!