Congratulations!!! That's fantastic news.
And just to add my 2c to the 'tell people or not' discussion upthread. For me, it depends on how well I'm coping with my own emotions about it, and how able I am to deal with anyone else's. My first four pregnancies I told as soon as I knew (and the first one ended in early stage miscarriage). This most recent one, I needed a good couple of weeks to get my head around it before making the information public. Heck, I wasn't sure how I felt about it myself yet, and I wasn't ready to deal with the excited congratulations squeals of some, the 'you do know what causes it' questions of others etc, when I was just as likely to laugh hysterically or burst into tears in response. Another friend, who is one of those "wants ALL the babies" types has had multiple miscarriages, (and has multiple children as well), and now keeps the information to herself because *her children* get really attached to the baby, and then are devastated if it miscarries.
So, it's a complicated issue, and everyone just makes the best decision they can with the information they have. (like ALL of parenting!) :)