Look at the array variable. As can be seen, the numbers used in the array are spread over separate lines. Here is the last part of the script:
Once the above code is decoded, it turns out be related to the Blackhole exploit kit which exploits a variety of known client side vulnerabilities. Here is a small screenshot of the decoded script:
Attackers keep registering different random domains to spread their attacks, often targeting free registration services. Due to obfuscation used by the attackers, security solutions relying on regular expressions designed to match known patterns can often be evaded due to the code being spread of over numerous lines.