Yes.
If you refresh the value of a coin, exchange or address by clicking 
(refresh), you will usually see 
blink, indicating the value has successfully been updated.
If you try to refresh the value twice or the value has already been recently updated, you will see 
blink, indicating that value refresh is rate limited.
Refresh rate limits prevent our servers from putting an undue load on our data sources' servers. We have decided to implement these rates as it is important to us to be a good crypto-currency netizen.