That said, you probably don't want to do this, because it contributes to blockchain bloat.
We made the decision of storing the data in a DHT because it's more efficient and you can store much more data than a few thousand bytes.
One thing I've still not grokked about your vision: What kind of redundancy can you expect for the DHT? It seems clear that, for the foreseeable future, there will be millions of copies of the bitcoin blockchain. How can you know that there will be a sufficient number of copies, distributed in a sufficiently diverse pattern, in order to ensure preservation of the DHT?
1. The replication factor of the DHT is set to be high.
2. We'll be committed to seeding the network and will work with others to have them run nodes.
3. We will provide a full index of the DHT, so the data can be retrieved via our API as an alternative to checking the DHT (the data can be stored and mirrored anywhere, since it's hash-addressed).
What incentive do they have to run nodes? Bittorrent has the tit-for-tat mechanism. IPFS is planning on incentivizing nodes with filecoin.
 - https://en.bitcoin.it/wiki/Alternative_chain#Objective
However, the vast majority of bitcoin blockchain "bloat" is from standard bitcoin transactions.
Financial and accounting data has always contained more than just integer values of credit and debit. Who, how, when and why are just as important to good bookkeeping as to what was transacted.
Blockstore, by creating transferable digital property in the form of a key/value store, creates an economic incentive to use Bitcoin. Right now, Bitcoin needs all the help it can get. Consumer adoption will not happen if Bitcoin is just trying to be a public ledger of integer values that attempts to compete with MasterCard and Western Union.
Thus you can expect continuing push-and-pull negotiations, perhaps requiring a separate system of continued payments, if you really want indefinite, reliable, unalterable storage.
Are you aiming for the "light-resolver" marketplace, or is this solution really for people who are already running full Bitcoin nodes?
Anyway, there's a somewhat detailed blog post that I helped write about light client design up on the Namecoin blog.
Are you seeding the DHT with your own machines right now? At web scale, wouldn't the number of machines participating in the storage network (as opposed to the blockchain) need to be huge?