The reason for WebKit is to be able to show a Google Maps frame to help people choose their location to get a more accurate sunrise/sunset. Not sure if that level of accuracy is necessary.
That said, the vast majority of OS X apps will link against the WebKit framework; not just Safari, but also Adium, Tweetbot, Mail.app, Growl, Notes, TextMate, iTunes, etc. It's pretty much guaranteed that it's in memory already, so there's no harm linking against it.
As for memory, ps reports about 64 MB of RSS; Activity Monitor reports 47.5 MB of memory used. Seems okay to me.
That said, the vast majority of OS X apps will link against the WebKit framework; not just Safari, but also Adium, Tweetbot, Mail.app, Growl, Notes, TextMate, iTunes, etc. It's pretty much guaranteed that it's in memory already, so there's no harm linking against it.
As for memory, ps reports about 64 MB of RSS; Activity Monitor reports 47.5 MB of memory used. Seems okay to me.
Which version of Mac OS are you using?