[sts9fan]

I have no choice, my only option to upgrade on my tvs speakers is a bar.
I want one that is powered with HDMI input. Recs?

[electricbear]

The soundbars by Polk are pretty decent but I'm not sure about the hdmi input. Yamaha have some nice soundbars also.

[radarnyc]

Vizio VHT510; buy from Walmart/other not direct. The subwoofer talks to the soundbar wirelessly and there are two wired rear speakers that connect to the sub. Works well enough and is a decent design.

[youravhandyman]

The Polk soundbars take optical or analog in but at least come with the optical cable.  I've not had a customer complain about the 6000 model sound. 
The Yamaha are very impressive but a bit large and could loose you the WAF.  If price is no object you might look at the Bose too.  Bob, don't kick me off because I used the B word.

The strongest soundbar I have heard without a subwoofer is the Atlantic Technology H Pas powerbar 235.  I'll throw a link on here for info.  This product has been showing at the trade shows for the past 2 years and has finally come to market.  http://www.atlantictechnology.com/default.asp?NodeId=170