The official website of Bitcoin Core, the reference client of Bitcoin initially developed by Satoshi Nakamoto, is currently displaying an alert about "Bitcoin's possible incompatibility with some major services."
In the announcement linked by the aforementioned alert, the Bitcoin Core developers attack the signatories of the New York Agreement (aka NYA), which was signed earlier this year by a significant portion of miners and Bitcoin organisations in order to end the so-called "scaling debate" through a hard-fork which will raise the block limit beyond 1MB.
According to the announcement authors, the planned hard fork which is the epicenter of the NYA, is rushed and hasty, and it has minority community support regarding both user and developer acceptance. Moreover, they accuse the supporters of the NYA that through the hard fork (scheduled to take place in November) they will be essentially shifting Bitcoin users to an altcoin, incompatible with Bitcoin.
The alert goes to warn current bitcoin holders that storing their BTC on specific services (such as Coinbase, Xapo, and Bitpay) which support the hard fork is not recommended because their bitcoins will be "renamed to something else or replaced entirely with the new alt coin." The use of web wallets, such as blockchain.info, is also discouraged.
Instead, the alert invites users to download the latest version of Bitcoin Core and immediately transfer "any BTC stored on services that are a signatory to this agreement."
The announcement goes on to list all the businesses which support the planned hard fork.