This is such a hugely important area for Cloud Providers to develop new services because of the double impact it represents.
First there is the simple facet of the business opportunity. Clients like governments and the finance industry have extensive requirements for archiving and e-discovery.
Secondly and the accelerating factor is that the biggest hold up to Cloud adoption is the lack of maturity in this area. Typically the fears all centre on issues like data residency, where is the data hosted, and what protections are in place to ensure this data is not tampered with and so on.
These are requirements that archiving solutions deal with straight off the bat.