This is something that's been going on for a while - Google killing small web apps; Convertors, calculators, movie listings, ip finders, weather stats, stocks. It's not all low-hanging fruit. I'm not saying they shouldn't be doing this, nor that it's intentional. Their goal is to be the best search engine which means connecting searchers with answers as quickly as they can. But even so, it sucks for the web apps who get made redundant by Google.
Also, it's interesting to compare this with, say, Yahoo's approach. Yahoo would have put an "IP" widget and a "weather" widget on their portal homepage. Google waits until the user searches for the info before giving it to them - which keeps their homepage clean and more importantly keeps their message strong "we do search well", while Yahoo's always seemed to be "we do a whole bunch of stuff, some of which you may need". I know Google/Yahoo comparisons aren't really du jour, but still it's interesting.