Skype certainly isn’t making itself any friends by blocking these clients. Both boast a large user pool. Nimbuzz is used by 30 million people, on Mac, PC and all major mobile platforms. That’s a lot of people who are finding themselves seriously annoyed at having to look elsewhere for Skype support starting Oct. 31.

I’ve already said that Skype is missing the boat by not prioritizing its Mac and iOS clients above those for other platforms. Skype’s iPhone efforts are one of its major sources of revenue, but now, I think it may be on its way toward being squeezed out of the Apple ecosystem. Even if Apple doesn’t lock it out entirely, as it has done with Flash on iOS, it could render Skype redundant by expanding its FaceTime efforts. In fact, even the planned North Carolina data center could be part of an effort to prepare for increased server demand resulting from FaceTime. Nimbuzz already announced that it would be bringing FaceTime to its client, and it probably won’t be alone.

FaceTime’s arrival on the Mac as a standalone app from Apple also can’t be good for Skype’s prospects. If I can do phone-to-computer or vice versa between Apple-branded products using Apple-branded software, I’m not very likely to go looking elsewhere for a solution. And if Nimbuzz and other multi-service clients expand that capability beyond just Apple-made devices, then I’ll have an end-to-end video and voice calling solution that covers all the bases.

Apple probably won’t move to actively block Skype, but it will give preference to its own solutions first and foremost, like it’s beginning to do on the Mac by not shipping machines with Flash pre-installed in preparation for the arrival of the App Store on OS X. Skype may find itself on the outside looking in, especially if they continue to alienate third-party apps that could guarantee them a continued presence on Apple devices.

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At first, I mistakenly inferred from the app description that it supports only Wi-Fi connections. Not so. For voice chat and VoIP functions, you must have a Wi-Fi connection, probably to comply with carrier-imposed limitations, but for text chat, 3G and EDGE are fine. Like Palringo, Nimbuzz! requires you to sign up for a master account, but the process is relatively painless. You can do it from within the application, and the only information required is your desired username, password, and a valid email address. Nimbuzz! uses the account to store your saved services, so you can sign in to the PC and web versions with a single login and access all your IM networks.

The interface is clean and fresh, with different icons for your contacts depending on which service they are from. You can add services from the “Communities” tab at the bottom of the screen, and also switch from your contacts list, to chats in progress, to your message inbox/sent and your settings. The “Messages” tab shows you your Nimbuzz! emails, which can be sent to and from Nimbuzz! contacts, and which stand in for offline messaging, as far as I can tell.

Touching a contact name brings up a screen from which you can call, initiate a chat with, or email that person depending upon what is supported by the service to which they belong. This screen also displays their email, nickname and status.

Chats and VoIP worked fine in Nimbuzz!, on par with Palringo and Fring in terms of speed and quality. Nimbuzz! is not a newcomer to the space, so I expected no less from them. Unfortunately, a deal-breaker for me is the lack of persistent connectivity. You are signed out of your services the moment you exit the app. It doesn’t even have the short delay Palringo offers, let alone Beejive’s 8-hour login duration. It is nice to see the polish and usability of Palringo with the VoIP features of Fring, but if you depend on IM for business and are away from a computer for much of the day, it can’t replace Beejive.

For casual users and as a VoIP/voice chat supplement to an always-on client, Nimbuzz! is a great choice. Overall, the interfaces are clean, responsive, and well-designed and the app in general has a slick, professional feel. Kudos to Nimbuzz! for not rushing out of the gates and sparing us another bug-riddled IM client for the iPhone. Try it yourself here for free.

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