1. A computer-implemented method for storing data, comprising: under the control of one or more computer systems configured with executable instructions, selecting a data storage device that is at least: comprised of data storage media that stores data sequentially; and capable of responding to a write pointer query by returning a write pointer that indicates a sequential last write position upon the data storage media at which data was most recently written; and in response to receiving a plurality of write requests, at least: caching data associated with the write requests in local memory of the computer system; sequentially recording at least a subset of the cached data upon the data storage media; and verifying, without flushing or committing the subset of cached data, that the data was written successfully by at least: querying the data storage device for the write pointer; and comparing the sequential last write position upon the data storage media indicated by the write pointer with a predetermined sequential destination upon the data storage media for the data being verified.