Trendistic is a tool that allows you to track trends on Twitter, similarly to what Google Trends does for Google searches. It gathers tweets as they are posted, filters redundant ones and compiles the rest into one-hour intervals.
This way, it shows how the frequency of one, two, three and four-word phrases fluctuate over time. The result is a visualization of what is popular and what is not among Twitter users, and how certain events are reflected or even predicted by themicroblogosphere.
You can enter a phrase (topic) in the Trendistic search box to see how its frequency varies over time, or several different topics separated by commas to see how they relate (each topic will show in the chart with a specific color): try comparing ‘dinner’ and ‘breakfast’ or ‘morning’ and ‘night’ for instance, to see how powerful it can be
1. Twitter Search: The simplest way to see trends on Twitter is on their official search page. Hot trends on Twitter appear on the search page and on the Twitter homepage, and clicking any will bring up a feed of the public conversation.
2. Twist: For those who are visual, Twist provides a graphical interface to see trends and keywords on Twitter. It not only lists out the hot trends over the last few hours, days, and week, but it provides embeddable charts and the ability to compare trends.
3. Monitter: Monitter is one of the best ways to track trends in real-time. Type in keywords and it will automatically update with the most recent tweets containing those terms. Add or remove columns to give you the right amount of information.
4. Hashtags.org: The popular webpage on Twitter hashtags also provides graphs on hashtag use just by hovering over the hashtag. There are also pages that show the most popular and newest hashtags, but their uptime is unreliable.
5. Tweetmeme: Looking for the most popular links on Twitter? Tweetmeme is the epicenter link sharing on the service.
6. Plodt: This website is a user-generated trend tracker based on tagging and ranking your tweets. It requires you to follow the Plodt Twitter account to participate. But even without participating, its timelines, tags, and statistics are still useful and interesting.
7. Twitturly: Twitturly is another way to track top-shared URLs. The interface allows users to see all of the active tweets that have shared a specific link.
Also for check Twitter Trends Topics While on the Go there is iPhone app for that
14. Twitter Trend [iTunes Link]: This free application provides a simple tag cloud for looking at hot, rising, or emerging trends on Twitter.
15. Summizer [iTunes Link]: Summizer is an advanced query Twitter search tool. It allows users to view trending topics or find specific types of tweets, i.e. Tweets sent by or from a specific person, or tweets that don’t include specific words. Summizer has both a paid and a free version.
Thanks to Mashable for the above list of Sites