Starting a social network... should I just start out with renting a dedicated server?

[harjanto]

Traffic will be relatively low for a few months, but I expect growth to be exponential within a few months; should I just start out with a low spec'd managed dedicated server (or go with shared hosting)?

Are there any hosts who can quickly upgrade servers in a timely manner if need be?

[Galaxy-Hosts.com]

If you have money you do not mind spending on the project, go dedicated right away. Keep in mind you may have to pay on the dedicated if your site does not grow as quickly as you hoped. Yes, there aer many hosts that can upgrade servers in a timely manner if need be. Also if you do start out with shared hosting, many providers will help you seamlessly upgrade to one of their dedicated server offerings.

[LSComputers]

As mentioned if you have the funds to start right away then I recommend one of two things:

Co-location + Server Management
Dedicated Rental + Server Management

You will want a server management to keep the site online and running smoothly.

A shared package would also work well for you.

If you have ideas or want some help, I can offer you some free consulting to help get this project of yours started.

[Richard]

You might want to look into a VPS, which is like a dedicated server, but can be quickly upgraded if you need it to be.

VPS plans start at around $10/month + a control panel (Most hosts provide a free control panel, for example, we provide ServerCP or HostInABox (lxadmin) for free on all our VPS's)

A VPS would make it that you do not have to spend much to start off with, but then could upgrade when your site becomes bigger.

[INVIHO]

First of all i suggest you not to start a social networking site if you dont have something , new fresh in mind a niche .... There dozens of SN sites that are dying now .. The fat ones like myspace, hi5 take all the pizza ;)
You should start with a dedicated server + management so you'll not have to go through moving process later.

[Hosting Advisor]

I would advice you to start in with some basic hosting plans and thereafter if you notice some relative growth. Move in directly to a fully managed dedicated server with the best of the configurations.

[stuffradio]

maybe for now a reseller account or a VPS. If after a few months it starts to grow a lot move to a dedicated

[rohitj]

Dedicated servers do not cost much and give you far more control in a shared environment. A few hundred dollars in managed hosting can go a long way in building your venture.

[fireshark]

For such a thing, don't go shared