Personally, I don't think so. The Bing webmaster tools are worth using if you plan on trying to rank in Bing/Yahoo, but Google will still hold the upper hand as far as competition goes.
I disagree. Bing Webmaster tools rocks. Sure, Bing is not a dominant search engine, is only going to provide a small proportion of traffic, but this does not mean that Bing WT is not worthy of consideration. They have taken huge strides recently to make Bing WT really useful, and do much less data obfuscation than Google do, so you get exact metrics rather than numbers rounded to the nearest 500! Lack of reach does not mean lack of data. Bing have plenty of resource to index and understand the web, and this data is available in Bing WT. A stand out tool at Bing is Link Explorer - anywhere else you have to pay for incoming link data. Bing provide it for free, not only for your site, but any site! (Diagnostics & Tools > Link Explorer.) The "Additional query" field can provide some really interesting link prospects. Sure, you don't get all the detail about the incoming links that you might need to prioritise efforts, but it's pretty easy to add this by exporting the data and using Google Docs to discover it. (use importXML) So, I'd recommend that you check out Bing Webmaster tools in more detail - there is plenty of useful information in there for webmasters.