UPDATE: Part II of this post, which includes the rest of my favorite 25 startups to watch this year, is now up.

I’m watching hundreds of startups, have at least one list of them over on Twitter (500 startups are on that one) and will be starting other lists in 2010 but I’ve been watching the trends on Twitter of what people are talking about and here are 25 startups to watch.

Why?

Because they are the best of breed examples of trends that are bigger than them. Is this list complete? No way, but it gives you a good starting point on some companies who you should be trying out and watching.

I have 15 other companies that I’ll be posting over the weekend, please let me know if you have any companies you are watching and we can watch them together.

1. Boxee. (Crunchbase entry). Twitter account. There are a ton of videos linked off of CrunchBase. Why is it important? Because better than any other company this one is pushing TV in a new Internet-connected direction.

http://blip.tv/play/AYGP0RQC
2. Vark. Crunchbase entry. Twitter account. My video with founders. Why is it important? Because it uses humans to get answers to questions that search can’t answer and it does it via an interesting distribution system via IM, mobile apps, and email.

3. Foursquare. Crunchbase entry. Twitter account. Why is it important? Because it brought us a new kind of game: a location-based one, but forget the game, when you check in with it you’ll see who is close to you and what tips about cool things to do near you have been left by your friends. Video of company founder on Gillmor Gang talking about Foursquare. UPDATE: a few people say I should put Gowalla (Foursquare competitor) on the list. But so far I went for Best-of-Breed and in my view Foursquare is kicking Gowalla’s behind. But, indeed, I’m watching Gowalla too.

4. Nextstop. Crunchbase Entry. Twitter account. Video of company founders demoing nextstop’s mobile. Watch a more general video overview with the founders. Why is this important? Because discovering interesting places to visit, whether in the places near where you live, or on a trip across an ocean, is something we still can’t do well. Nextstop brings us a way to share, curate, and collect interesting places.

5. Rippol. Crunchbase entry. Twitter account. Video of Rippol’s founders showing off several new features coming next week. Why is it important? Because it shows off something I expect a range of new companies to do in 2010: display a different view of our social networks, in this case it will show you just videos that your Twitter and Facebook users are sharing. I find it invaluable for watching large numbers of users and the videos that they care about.

6. Waze. Crunchbase entry. Twitter account. Video demo of Waze as we drive around Palo Alto. Why is it important? Because it shows off how crowds can be used to compete with much bigger companies, but also how mobile devices can be used to share information with each other to build a new kind of service that isn’t possible other ways.

7. Gist. Crunchbase entry. Twitter account. Video of Gist’s founder on my studio show about future of work and a separate video of my visit to their headquarters in Seattle. Why is it important? Because when you are working with people the more you know about those people the more productive you’ll be able to be. This is particularly true for salespeople and other networkers. Before you make a big call, have you checked all their social networking sites to see what they’ve written? With Gist it’s easy and hooked into your email system.

http://blip.tv/play/g8sRgbX_QQI%2Em4v
8. Kynetx. Crunchbase entry. Twitter account. Video with founders explaining why Kynetx is an interesting real-time development system. Why is it important? Because it lets developers augment websites and search engines for their customers. AAA can add new data to Google.com for its members, for instance.

http://blip.tv/play/g8sRgajiFAI%2Em4v
9. Tapulous. Crunchbase entry. Twitter account. Video with Tapulous’ founder talking about having the top grossing iPhone game. Why is it important? Because mobile devices are changing how we play games and the company that best took advantage of that trend in 2009 was Tapulous who had the #1 iPhone game and was first to introduce in-app buying of virtual goods, another trend I expect will be huge in 2010.

http://blip.tv/play/g8sRga3gOQI%2Em4v
10. Posterous. Crunchbase entry. Twitter account. Video of company founders talking about how Posterous makes publishing simple. Why is it important? Because, while Twitter has made publishing short messages super simple sometimes a short message isn’t enough and you want to write a blog, or post a video, or put up a photo. Posterous is one of a handful of companies that have pushed publishing along in 2009 (Tumblr is another one) and that makes them a company to watch in 2010.

More to come later this weekend.

I have kept a database of my favorite 11,000 tweets, all gathered in 2009. In fact, all gathered since June.

A service named Favstar has kept track of who are my favorite twitterers.

My favorite tech team who Twitters? Techcrunch.
My favorite tech twitterer? Dave Winer.
My favorite top 10?

1. Techcrunch
2. Dave Winer
3. Mashable/Pete Cashmore
4. Mike Arrington (founder of Techcrunch, his personal account)
5. Read Write Web
6. Tim O’Reilly
7. Y Combinator News
8. Venture Beat
9. Louis Gray
10. Guy Kawasaki (a team of three that tweets along with Guy).

Personally, though, I love the whole list. It reads like a “who’s who” in Tech with thousands of people on it who have received a favorite from me in the past six months.

Another thing to watch in 2010 will be the rise of Twitter lists and curators who pick people for these lists. For instance one of my favorite new places to find Twitterers is Listorious (a service that didn’t exist a year ago) and its technology lists are very good places to see how Twitter is changing the tech world. I bet that the top tech twitterer of 2010 is already on one or more of the lists that are there.

One last fun thing to do is to compare my favorite tech twitterers with the Techmeme leaderboard. You’ll see most of them are pretty similar but there are some sizeable differences and it’s in those differences that you can detect both my biases and those of Techmeme’s choices. What do you see when you compare these two lists? (My Twitter list is far more biased toward people, than just brands, for instance).

Anyway, 2010 in real time tech news will be fun to watch. How are your reading experiences changing?