When it comes to Twitter, I've been using Twitterrific from jump. Sure, I've tried every other Mac OS X offering, but have never been able to stick with one for more than a couple of days (until TweetDeck; keep reading). The main reason for this — apart from Twitterrific's good looks and ease of use — is that no other client offers Twitterrific's last-tweet-read/seen feature (i.e., a placeholder at the last read tweet). I find this mind-boggling because it seems so trivial to implement, and it weirds me out that more people aren't clamoring for it in all the other clients. Why would anyone ever want to spend any time trying to figure out where they left off when last they checked their Twitter stream?
That said, Twitterrific is pretty bare-bones and hasn't seen a significant update for close to a year, and as you might suspect, the competition hasn't been sitting on its ass. Like I said, I've played around with every available client, and while none provides last-tweet-read "bookmarking," many do offer features above and beyond those found in Twitterrific. TweetDeck, my current daily driver, allows customizable columns that really help me to make the most efficient and practical use of the micro-blogging service (especially when the app is full-screened in its own space, an implementation even Matt Haughey might be able to get behind). From the product page:
TweetDeck enables users to split their main feed (All Tweets) into topic or group specific columns allowing a broader overview of tweets. The default columns can contain All Tweets from your timeline, @replies directed to you and direct messages. The GROUP, SEARCH and REPLIES buttons then allow the user to make up additional columns populated from the live tweet information.
While TweetDeck's ability to sort tweets into columns is what makes it so much more useful than anything else I've seen, the execution of the feature is fundamentally flawed because tweets show up in every applicable column. As an example, assume that I've a "main" column for all tweets from people I follow, a @replies column and a column to hold a group I've created for real-life friends. If a real-life friend sends me a @reply, it will show up in all three columns! This isn't so annoying as to completely outweigh the benefit of the app, but damn if it doesn't make me crazy to have to read the same tweet three times (or rather ignore it twice).
I'm hoping this will be "fixed" soon, assuming, of course, that the developer agrees it's an issue. The way I see it, a hierarchy should determine where a "multi-column tweet" appears, something like: direct message > @reply > search > group > all tweets.
Also, as I mentioned, TweetDeck doesn't offer last-tweet-read, and so to keep up with the stream you kind of have to clear everything after you've read it (so you're not trying to figure out where you left off when next you return to the app). At the tweet level, TweetDeck's mark-as-read functionality is laughable (it's a micro-sized "dot" placed too close to other clickable things); at the stream/column level it's a bit better, but there's 1) no way to clear all tweets, only "clear seen tweets," which means you have to click two buttons for every column (i.e., "mark all as seen," and "clear seen tweets"), and 2) there are no keyboard shortcuts. Ideally, I'd like to read a column of tweets, and then hit a single key sequence to clear the read column (or better yet, clear all columns).
(Iain, I write because I care. Keep up the good work.)