Just a few hours ago we're reporting on those new features in Seesmic v1.3 and now it's live in the Marketplace.
Although we gave some flack to the Twitter Racoon for no push updates, we'll applaud their team for this: Seesmic v1.3 is hands down the fastest Twitter app now on Windows Phone 7. It is very zippy and we even had our own 'Neo' moment with an audible "whoa" when launching it. (Too geeky?)
Besides the very impressive speed updates and unmentioned bug fixes, not much else has changed, including no landscape support, no conversation view (gah!). It also still doesn't run under the lock screen, so you get that 'resume' thing happening (double gah!). Oh, but there is that new Tile art above.
But hey Seesmic, you have a solid base going right now for your WP7 Twitter app--let's get some landscape support, run-under-lockscreen and push notifications going and you'll own this race. Twitterers: grab the update now.