I used to use Network Solution's (NetSol) website to check the availability of domain names as it allowed me to type in a list of domain names in one go.
Up until recently, this had been fine.
Recently I did this as usual and when I chose the domain name I wanted to register I attempted to register it with another domain name registrar.
Strangely the other registrar said that the domain name had already been registered. I checked again with Network Solutions and it said the name was still available.
I investigated further and found that the name was just registered to Network Solutions.
Further investigation revealed that Network Solutions take advantage of a facility available to all registrars called "Domain Tasting". This allows them to register a domain name for up to 5 days without paying for it, then they can choose not to pay for it and the name will be released.
I read elsewhere that Network Solutions increase the price to register the domain name over the next few days in an attempt to scare you into buying the domain name immediately.
So you have been warned. When you do a domain name search with Network Solutions they will register that domain name immediately, whether you end up registering with them or not. And if you choose to register it with another registrar you will have to wait at least 3 days.