Webs was acquired by Vistaprint in 2011— and since then the company has maintained both products.
Webs has become increasingly out-of-date: there are no responsive themes, and no feature or UI changes are on the horizon. The Webs Announcements blog hasn't had an update since 2014.
These are signs that Vistaprint's attention has turned to the Vistaprint website builder— and away from Webs.
This has not been communicated to Webs customers— which sucks. I hope they communicate it soon. Acquiring products and abandoning them is common in website builders. When GoDaddy acquired Virb, Virb's customers stopped getting new features and the product has stood frozen in time. I hope this does not happen to Webs customers.
Vistaprint assures me that they are not bailing on Webs users. They still offer support (including phone support to higher tiers) and are investing in server infrastructure. But in the meantime, I wouldn't recommend new users to choose Webs.