Some more points to consider... (Score 1)

Full Disclosure: I work for a (Great!) data center provider (ViaWest ).

Infrastructure:
- What is the UPS run-time?
- What is the generator startup time?
- What is the genset capacity in relation to UPS demand? (i.e. is the UPS demand larger than the genset capacity - you'd be supprised!)
- Does the provider have multiple refueling contracts?
- Are the refueling contracts high priority?
- Can the provider detail out green initiatives to improve PUE?
- Does the provider have sufficient capital resources to expand the data center?
- How much investment has the company made - this year - into the data center?
- Is the data center in a flood plain? Check http://msc.fema.gov/

Compliance:
- Is the data center SAS-70 type II audited? Type II means they're serious about it.
- Are the results of the audit available for review?
- Are a list of control objectives available?
- How does the provider assist with customer audits? (i.e. PCI auditor requests for info)
- Can the provider demonstrate servicing other companies where compliance is a requirement?
- Will there be additional charges for audit related work or requests?

Network Remote Hands
- Does the provider offer managed hosting / hybrid hosting options
- What is the expertise level of the NOC staff?
- How are remote hands charged?
- What is the response time for a remote hands event?
- What monitoring options are available?

Corporate
- Does the company have a business continuity plan documented?
- Are the company financials available for review?