1000 txs/sec might be referencing the total of transactions happening on the Tangle (sum of txs/sec of all Nodes). The number of txs/sec a Node receives depends on three things:

<li>How many light nodes are connected (and submiting transactions) to it</li>
<li>How many transactions it is receing from its neighbors</li>
<li>Download Bandwidth</li>

We can see that the txs/sec a node receives is a value that changes from Node to Node depending on its specs. The number of txs/sec a Node can push to the Tangle depends on its upload bandwidth.

From comments bellow:
> how many of these transaction will be seen by a full node with a "standard" setup?

An average transaction in IOTA has [1.6Kb](https://domschiener.gitbooks.io/iota-guide/content/chapter1/transactions-and-bundles.html), a network with 1000 txs/sec would be pushing 1.6Mb/s to the Nodes. It's not a value that high, a standard setup could handle it. Even though if a Node couldn't handle it, the network is asynchronous, it means that the Nodes [don't have](https://www.iota.org/IOTA_Whitepaper.pdf#page=3) to see/view the same set of transactions

@edit: resumed the comments below here.