Gmail might turn out to be real.
For: This is Google's April Fools hoax:
Google is interviewing candidates for engineering positions at our lunar hosting and research center, opening late in the spring of 2007. This unique opportunity is available only to highly-qualified individuals who are willing to relocate for an extended period of time, are in top physical condition and are capable of surviving with limited access to such modern conveniences as soy low-fat lattes, The Sopranos and a steady supply of oxygen.Also, a quick Whois reveals that the domain name does indeed belong to Google.
Against: A few cynical Slashdot readers are pointing out these facts:
i. The press release is dated 1 April 2004 UTC, but the usual Google press releases are dated without time-zone;
ii. When the Gmail site went live initially, its logo did not contain the TM sign.
Instead of sitting on the fence (like this blogger), I am going to make a call: I think it's for real.