Yes. In fact, Blizzard has this to say about these...
"As the Beta-testing period draws ever nearer, so too do the nefarious machinations of those who would like to separate you from your account and use it for their own ill-gotten gains. With the excitement reaching a fevered pitch, even those who normally would be more cautious before responding to a phishing email may drop their guard. This is exactly what account thieves are depending on.
To that end we'd like to remind you anew of the need to be cautious before responding to emails purporting to come from Blizzard Entertainment and provide some resources for you to educate and protect yourself.
BLIZZARD WILL NEVER, NEVER, EVER ASK YOU TO REVEAL YOUR PASSWORD.
Even emails that contain @blizzard.com or @battle.net in the "From" address may be fraudlent, as it is quite easy for phishers to spoof email headers to make it appear as if the email is originating from us. Luckily, there are ways for you to unmask their underhanded tricks:
How to Spot Fraudulent (Phishing) Emailshttp://us.blizzard.com/support/article.xml?locale=en_US&articleId=25133
In general, any email you get that is offering you a beta key is almost certainly a fake. Some telltale signs of fraud are:
- Poor spelling, grammar, and/or syntax
- Requests for you to submit your account information
- Someone messaging you in any Blizzard game claiming to be an employee
The absolute sure-fire way to tell if you have been selected for the beta is to log on to your Battle.net account by manually typing https://us.battle.net/account/management/
into your web browser's address bar. If you were selected, then a Diablo 3 beta license will be automatically added to your account and you will see it listed there. You will not need to do anything other than download the game client.
The only exception to this rule is if you received a beta key from a legitimate promotion (game store, contest, etc.) and you physically have the code with you. To claim this code, enter it at https://us.battle.net/account/management/add-game.html
If you have any questions about the legitimacy of any email you receive, please feel free to post here in the Tech Support forums for analysis."http://us.battle.net/d3/en/forum/topic/3123364781