Originally Posted by newbreed

The answer is yes, but it you use one database, you'll be limited to the plugins and template of that ONE database.

Also, you'll need to maintain one Admin section.

Content on each blog would obviously be the same as well.

Originally Posted by HomerSimpson

you can use only one database

in wp-config.php there's a setting for table prefix
$table_prefix = 'wp_'; // Only numbers, letters, and underscores please!

all you need to do is change it
and there you go...