There were many changes that happened on the farm after that miraculous morning when Lurvy saw "Some Pig" written in Charlotte's web; however, I think the three most important were that the farm was now crowded with visitors, the Zuckermans' and Lurvy's normal behavior changed, and the farm chores were forgotten.
First, there were many visitors that paraded onto the farm every time a new word was discovered in the web. This meant numerous cars, people, and noise where it once was quiet and peaceful. Fern missed having the barn to herself and Wilbur became exhausted from all the publicity, but he still tried to put on a good show for his audience.
Also, the Zuckermans and Lurvy changed their normal behaviors to impress Wilbur's visitors. They wore their Sunday best clothes every day and Mr. Zuckerman even had Lurvy put straw in Wilbur's pen so that he wouldn't get dirty from the manure. Sadly, the straw scratched Wilbur and he wished he could go back to his beloved manure pile.
Finally, since the Zuckermans and Lurvy were so busy with their visitors, they didn't have time for the normal farm chores. The berries weren't picked and no jam was canned for that year. The garden became overgrown and the fields weren't harvested.
Therefore, once Charlotte's words "Some Pig" and the subsequent messages in the web were discovered, normal life on the farm halted. Since everyone wanted to see Zuckerman's famous pig, the farm was now crowded with visitors, the Zuckermans and Lurvy changed their normal behaviors, and the farm chores were left undone. These are the three most important changes that happened because Wilbur was "Some Pig," "Radiant," and "Humble."