You may also want to take a look at Twicca. A bit of a "up and coming" app slowly gaining popularity. Their widget is free and it has a nice functional look with color labels.
Touiteur is a very nice app, along with the developer who is always updating the beta and pushing out new market updates pretty frequently. He also listens and opens up voting for new options etc to be added. Very nice app.
Premium gives you no ads and multiple account support. As well as more customization options and the widgets. Well worth it for like $2-3, comes HIGHLY suggested.
Let us know how you like it! I have heard nothing but good from that app, the dev is highly supportive and active too, so nothing but good things to say about him as well.
So I purchased touiteur. I like it so far. The large widget is alright but definitely wish it was better. It could use a scroll feature kinda like peep has and not just a button that flips to the next 5 tweets. That's kinda a joke in terms of a feature haha.
Other than that the rest is good. Oh and also I've seen problems with the refresh. My interval is on 15 minutes but today I tweeted, put my phone away for an hour (in sleep mode or whatever) and turned it back on only to click the app and see that it hadn't refreshed since my last tweet. That kinda irked me
Each to his own, but I would rather not having it fetch stuff unless I want it. Another thing to remember too, is that your network is cut off when it goes into sleep mode when on WiFi. I just set it to refresh when launched and it's the same as.