Summary
When opening a new Stripe account it can take up to 7 days for the first transfer to post. Stripe puts the transfer through a run to ensure accuracy, correct routing to the correct bank, the funds aren't being transferred overseas, and so on. Once everything is considered "okay" the following charges usually post within 24-48 hours.
Key Points
This delay allows Stripe to mitigate some of the risks inherent in providing credit services
You do not have to wait the 7 days for that first transfer to post before accepting more payments.
More information can be found at Stripe's website.