I just thought about it this morning. I don't have a texting plan on my Focus, so I never thought I'd have to deal with it, but this morning I was trying to do something on Twitter and couldn't get my keyboard to stay up. I can't imagine how frustrated you all are. I definitely hope that gets fixed soon.
Also, I asked my sister about this and she said she's never noticed it on her mango-upgraded Trophy. Could it be device-specific? Or is it just a random bug?