Or heck, even Twitter for that matter? In the meantime, a little cottage industry of Twitter-focused services has sprung up. Noticeably absent is Google. I can't tell if that's some sort of Jaiku-in-the-waiting move, or no move at all. Perhaps they're waiting for someone else to get it right so they can buy them. No doubt, getting Twitter search right is probably harder than it seems. Most of the sites I've found are pretty sloppy.
Frankly, I don't use many of these since all these Twitter pieces are too fragmented and formative for me to remember to bother.
Still, here's a quick review of the stuff I've tried lately:
Summize 
By far my favorite search, Summize replaced the now-defunct Terraminds as my #1 Twitter searching buddy.
All my RSS Twitter searches are driven from Summize. It's even got some other nifty features like showing threaded conversations, trending topics (memes), "nifty queries," multilingual support, and an easy way to tweet your search results. I also love that Summize doesn't use the word "Tweet" in it's product name. It's why I can't remember most of these, they sounds exactly the same.
Outside of my iPhone client, Summize is by far the best Twitter search/stats app on the market.
Tweetscan 
I do give serious credit to my old Twitter search engine, Tweetscan, for flaunting their eco-friendly toilet advertisement on their homepage but other than that, they lost me.
The site needs some UI love. The colors remind me of the 1990s Mint and Teal craze, which makes me want to shower. Upon closer look they display popular searches and upon looking again, I found the toilet even nicer than the first time I saw it. I mean, it's pink and ecofriendly.
That's one kick ass toilet. I might return now that I found that.
Quotably 
I had high hopes for Quotably. It's supposed to help you follow Twitter conversations but I find that it doesn't work any more practically than Twhirl, which I use for my desktop client. There's no doubt that following conversations on Twitter can be very hard but the results in Quotably are mostly inaccurate and don't lend themselves to being any more practical than searching for your replies and using your memory.
I guess if you have no memory, Quotably could be ok for you. I've typed, "where are my keys" a few times in it's search box but it didn't help me remember where I put them. And there's still no way for me to put an RSS feed on my keys as much as my wife would like to engineer one.
Tweetstats 
I wish I had a need to use Tweetstats site more. It sure is purty. Friendly, too. And it makes some interesting graphs. How can you not like a site that says, "There be faeries" while you're waiting for the results? And I believe that it's powered by creatures, so don't tell me it's a lie.
Most of the graphs I find novel more than useful. Who cares which hours I'm most active? What am I supposed to do with that, amp up my activity between 4am-6am? I do like the graph that shows who I talk to the most. It's the only one I find interesting.
I recently discovered that there's a "tweetclouds" button at the top which shows you a not-as-pretty but still interesting rendering of your activity.
Tweetclouds 
Anyone who reads this blog knows I'd like the Tweetclouds service. I was cut and pasting to create clouds before this thing came along.
I've noticed that they've fixed a lot of their instability problems (no one could get on the site for a white) and that they've added some of the Many Eyes features like two-word clouds as well as nifty things like "@" suppression.
I'm not sure why no one is yet doing trend-clouds. I want to see a living cloud over time. Imagine time lapse clouds which show if one word is growing or shrinking. I want to see the patterns. And I want to be able to have it as a living thing on my blog.
iTweet 
While I'm naming off Twitter services, I might as well include a phone client. I've played a heck of a lot of iPhone clients and iTweet is my current favorite (with Hahlo a close second).
All that said, I still hate tweeting on my iPhone. The EDGE network is slow and typing is a pain. And all the Twitter clients on the iPhone fail to be able to page ahead on your timeline (supposedly that's a Twitter API problem and not a phone problem).
I like iTweet's way oversized buttons and easy menus. I have massive paws so having big targets makes me a happy boy.
As an aside, I recently learned from Shel Israel that he and I have both nearly totaled our cars while tweet-n-driving.