Amazon.com has begun taking preorders for three Marvel RPG products due for release beginning in June.  The first product is the Marvel Universe Roleplaying Game Guide, a 128-page, $24 hardcover to be published by Marvel Books in June.  Creative staff is listed as Mark Beazley and 'Marvel Staff.'  Next up is the Marvel Universe Roleplaying Game:  Guide to the X-Men, a 96-page, $19.99 hardcover slated for release in July, with the same creative credits.  And last is the Marvel Universe Roleplaying Game:  Guide to the Avengers, another 96-page, $19.99 hardcover, slated for release in October, same creators listed.  Marvel did not respond to our request for more information prior to publication of this article.