What are the best features the online SEO tools like WebCEO, SEOmoz, Raven SEO, Hubspot, etc. have?

I can provide some feedback we've heard about our tools and what those who've canceled our subscription and switched to Raven-SEO-Tools or Hubspot have said (my answer is likely to
have a natural moz-bias, so please keep that in mind when reading).

SEOmoz - the Good:

• Good metrics - highest correlations with rankings of any in the SEO world (as measured against Google US rankings). This also generally means that our metrics match up intuitively well against sites/pages in the SERPs.http://www.seomoz.org/blog/the-s...
• Good toolbar - people express a lot of satisfaction with the mozBar for Firefox and Chrome (though there are complaints about the Chrome toolbar's overlay, an unfortunate reality because Chrome doesn't support embedded toolbars well).http://www.seomoz.org/seo-toolbar
• Open Site Explorer - a usable, useful way to get link data about nearly any page or site on the web (that has substantive links). The tool has been improving as data quality and freshness have risen. It's often mentioned by our members as their favorite feature. http://opensiteexplorer.org
• Q+A - although answers take 3-4 days to get answered, most of our members give us very positive feedback on the Q+A section. We'll often spend lots of time working through tough problems, providing ideas, suggestions, links, even connecting people with others in our network to assist.http://www.seomoz.org/qa
• Web App - the weekly crawls, rank tracking, traffic data and link information are all integrated, along with recommendations. Our newer members seem to be big fans of this. http://pro.seomoz.org
• We have 14,000 paying subscribers (as of Oct. 2011)- a little over 50% stay 18 months or longer and about 25% only stay 1-2 months. If you're an SEO professional or someone who does lots of work with content, links, search engines and social media metrics, Moz is likely a great fit. If you're more casually in the space, our tools can be helpful, but it might not be ideal over the long run.

SEOmoz - the Bad:

• Link data - when a new site launches, Yahoo! Site Explorer or GG WM Tools often has link information 20-30 days before we do. This can also be frustrating if you've recently built links and want to see their impact on our metrics ASAP. We're also not as comprehensive as we should be with 40-50 billion pages in index vs. Google/Bing's reports of keeping ~110 billion.
• Beta Web App - being in beta means there's still occasional errors, downtime (much more rare now) and key features missing (exports of CSV data on specific types of pages, white labeling, etc.)
• Labs Tools - some of our more advanced members do like these, but they're not nearly as usable, pretty or polished as the rest of the toolset and many tools that are useful have been in Labs a long time.
• Legacy Tools - some of our older tools haven't been replaced in a long time, and are in desperate need
• Made for Intermediate+ SEOs - The moz software is really geared for SEO professionals and can be tougher to pick up for those in the broader web marketing field who are just dipping their toe into SEO. We also don't yet have great onboarding materials/guides to walk through how to use and apply the tools step by step.

Raven - the Good:

• Large numbers of tools inside the system - they have a great number of tools that provide a wide array of functionality. Virtually everything one might want to do with a few exceptions (e.g. crawl errors/warnings data)
• White labeling - many say this is their favorite Raven feature and switch away from SEOmoz because of it. It's particularly useful to agencies and consultants who want to look like the source of data to their clients.
• Lots of third-party data - SEOmoz's Linkscape data, Majestic SEO data, SEMRush and others are all integrated with Raven, making it more of a one-stop-shop than SEOmoz, which relies mostly on its own metrics and data sources. http://raventools.com/tour/
• Thousands of Members - I don't know precisely how many folks use Raven today, but I believe it's above 2,500 and below 5,000. Given the recency of their entrance to SEO software, that's tremendously impressive.
• Great team - even though we're competitors, I am really impressed by the great people at Raven. Their professionalism, humility and personable nature has made big fans out of all of us at SEOmoz.http://raventools.com/about-us/

Raven - the Bad:

• Since they're a direct competitor, I'm loathe to say much here (why would you trust my opinion!?). However, when we've seen folks switch over to SEOmoz from Raven, they generally say they do it because they like our content, our link data and link analysis tools, our brand and specific pieces like Keyword Difficulty, Open Site Explorer or the Web App (particularly the crawl diagnostics data).

Hubspot - the Good:

• Holistic approach - Hubspot is not really an SEO toolset, but rather an inbound marketing software. It manages your CMS, your analytics, your email marketing messages, your blog and everything in between (for the installed version at least). This integration is truly powerful as it can guide you through a whole marketing process, not just SEO stuff.
• Ideal for beginners - Hubspot's audience often centers on small business owners who don't have tons of time to invest learning about web marketing. The Hubspot product really helps to explain simply and make the process logical and regular without massive time investments.
• Helps manage your pages - because Hubspot actually produces your pages through the CMS, they can do a great job making sure nothing's messed up or done wrong. Raven and SEOmoz can point out these errors, but can't really prevent them.
• 4,000+ customers and tons of market attention/interest. The startup world and the press are both big fans of Hubspot, and customers have been joining and sticking with them a long time, another indication of a great company and product.

Hubspot - the Bad:

• Not for SEO Experts - Hubspot readily admits that SEO gurus/experts aren't their audience and the product isn't geared toward them.
• Not easy to Cancel - Hubspot's an addictive product once installed, and like Salesforce or InfusionSoft, it's got your data and your system for producing content, so cancellation is much more painful (this is also a positive in that it often means you don't need additional software to fulfill those needs).