I don't see how Salesforce could get much value out of Twitter. They could get it out of LinkedIn (sales people use LinkedIn sales navigator a lot), but likely not at the price Microsoft has paid for LinkedIn.
You know what would make for a better acquisition? Amazon.
Twitter has tons of customers, tons of dark fiber, lots of internal cloud technologies (mesos, etc.) and a huge international peering network of IP routers.
Amazon needs a way into social and real time news.
Why does Amazon need this?