Okay, so the shine is off the Apple, so to speak, and we know what the iPad 2 is going to offer. Here are some things you need to know:
1) The "3G" model is really two different models. There is a Verizon (CDMA) version and an AT&T (GSM). So don't expect to buy "the 3G" version and decide which vendor to use with it later. You need to decide before you buy.
2) You cannot pre-order the iPad 2 at the online Apple store. Although Apple took their store "down" during the announcement, there are only product descriptions online now. You cannot put an iPad 2 in your shopping cart. So presumably, you will have to go to an Apple store at 5pm on March 11th if you want one that day. You can place an order online starting March 11th, but Apple offers free engraving so that's a nice benefit (in addition to free shipping) if you can wait.
3) The Personal Hotspot feature in iOS 4.3 requires an appropriate contract from your wireless provider.
4) The white iPhone has been delayed repeatedly. One of the alleged reasons was that the white casing allowed too much light in, which affected the camera. You might want to see how photos taken with the white iPad turn out.
5) Your existing iPad's case most likely will not accommodate the iPad 2. Aside from being thinner, with a flatter back, you need an opening for the rear camera. Depending on the case, a hole punch might do the trick!
6) Apple's new covers are interesting. They will have a (PRODUCT) RED version, with proceeds that benefit the Global Fund to fight AIDS in Africa but alas it is only available in leather. So you're helping one cause while hurting another. Besides, as the Apple website says "The leather Smart Cover is crafted from high-quality, naturally treated material that gets its color from a rich aniline dye. Some color may rub off during use." So, I might stick with the Polyurethane cover or see what enterprising manufacturers are able to come up with.
7) There are indeed two cameras, capable of shooting video, but keep in mind that the front-mounted camera is VGA quality.
8) Many of the features that were announced will also work with your older iPad. So it's not a given that you have to upgrade. For example, the $39 HDMI cable, dubbed the "Apple Digital AV Adapter" works with the original iPad, iPhone 4 or 4th gen iPod touch.
9) In addition to cellular data, the 3G models have Assisted GPS. If you plan to use location-aware apps, even if you don't plan to use a 3G data plan, you may want the 3G version.
10) If you don't have an iPad yet, the original (refurbished) is being sold for as low as $349 on Apple's site!